What is faith?

What is faith?

Updated October 22, 2026

A note from your group

Faith is “the assurance of what we hope for and the certainty of what we do not see”: believing the LORD, as Abram did. In Hebrews 11:1, the Greek word is pistis (G4102): trust: being persuaded that someone is true, and relying on them.

Get DeepWord
Your English Bible says “faith” over two hundred times, almost all of them in the New Testament. Behind it stand twelve different Hebrew and Greek words. First the answer from seven verses, then one original word from each.
Faith is “the assurance of what we hope for and the certainty of what we do not see”: believing the LORD, as Abram did.
From Hebrews 11:1 and Genesis 15:6.
Hebrews 11:1
BSB
Now faith is the assurance of what we hope for and the certainty of what we do not see.

What the original says

πίστις
pistis (PIS-tis)
Strong's G4102

Behind the word “faith” in this verse is the Greek word pistis (said PIS-tis).

It means trust: being persuaded that someone is true, and relying on them.

Here it is a noun, a naming word, and the subject of the sentence. Word for word it begins ‘is now faith’; the Berean puts it in English order, “Now faith is”.

In the Berean Standard Bible, it is ‘faith’ 234 of its 242 times. Once it is ‘proof’: God “has given proof of this to everyone” (Acts 17:31). And 3 times it is ‘faithfulness’:

Word by word
Ἔστινδὲπίστιςἐλπιζομένωνὑπόστασιςπραγμάτωνἔλεγχοςοὐβλεπομένων
isnowfaithof things hoped forsubstanceof thingsevidencenotbeing seen
Original form
πίστις
pistis

What this tells us

Hebrews is written to believers who were tempted to give up. Just before this verse the writer says, “we are not of those who shrink back and are destroyed, but of those who have faith and preserve their souls” (Hebrews 10:39). Then he stops to say what faith is, and spends a whole chapter showing it in people. The word behind “faith” is pistis: trust, being persuaded that someone is true and leaning on them. Here it has two sides. It is “the assurance of what we hope for”, standing firm on a promise not yet kept, and “the certainty of what we do not see”, being sure of what is real but out of sight. The chapter then fills the word with lives. “By faith Abel offered God a better sacrifice than Cain did” (Hebrews 11:4). “By faith Abraham, when called to go to a place he would later receive as his inheritance, obeyed and went, without knowing where he was going” (Hebrews 11:8). Faith in this chapter is not a feeling of certainty. It is people acting on what God said. Many of them, the writer admits, “died in faith, without having received the things they were promised” (Hebrews 11:13). So faith may not feel like certainty at all. It may look like setting out without knowing where the road goes, because you trust the One who called you.

Genesis 15:6
BSB
Abram believed the LORD, and it was credited to him as righteousness.

What the original says

אָמַן
aman (ah-MAHN)
Strong's H539

Behind the word “believed” in this verse is the Hebrew word aman (said ah-MAHN).

Its basic sense is to be firm and sure, something you can lean on. In this form it means to believe: to count someone firm and rely on them.

This form, he’emin, means ‘he believed’. It is joined to ‘and’ (וְ).

In the Berean Standard Bible, it is ‘believe’ 34 times, ‘faithful’ 14 and ‘trust’ 11. Isaiah 7:9 uses it twice in one line: “If you do not stand firm in your faith, then you will not stand at all.” It is even ‘nurse’, someone who holds a child (Ruth 4:16):

Word by word
וְהֶאֱמִןבַּיהוָהוַיַּחְשְׁבֶהָלּוֹצְדָקָה
and · he believedin · the LORDand · he counted · itto · himrighteousness
Original form
וְהֶאֱמִן
vehe’emin

What this tells us

Abram has been promised a family, and years have passed with no child. In a vision God tells him, “Do not be afraid, Abram. I am your shield, your very great reward” (Genesis 15:1). Abram answers honestly: “O Lord GOD, what can You give me, since I remain childless” (Genesis 15:2). So God takes him outside and says, “Now look to the heavens and count the stars, if you are able” (Genesis 15:5). The word for “believed” is aman: to be firm, to count someone firm and lean on them. Abram cannot see a single child, only a sky full of stars. He leans his weight on the One who spoke. And God counts it: “it was credited to him as righteousness.” This one line runs through the New Testament. Paul quotes it: “Abraham believed God, and it was credited to him as righteousness” (Romans 4:3). So does James, who adds that Abraham “was called a friend of God” (James 2:23). Paul uses the line to show that God counts trust as righteousness, and James to show that real trust shows in what a person does; Christians have long read the two together and weighed them in different ways. The word ‘amen’ comes from the same Hebrew root. Abram’s faith began with an honest question and ended with him looking at the stars. What has God said that you could lean on today, even while you still see no sign of it?

Habakkuk 2:4
BSB
Look at the proud one; his soul is not upright— but the righteous will live by faith—

What the original says

אֱמוּנָה
emunah (eh-moo-NAH)
Strong's H530

Behind the word “faith” in this verse is the Hebrew word emunah (said eh-moo-NAH).

It comes from aman, the word you met in Genesis 15:6. It means firmness, steadiness, and so faithfulness: being someone others can rely on.

This one word has three pieces: בֶּ ‘by’, אֱמוּנָת ‘faith’, and וֹ ‘his’. Together: ‘by his faith’. The Berean leaves ‘his’ out and says “by faith”, as the New Testament does when it quotes the line.

In the Berean Standard Bible, it is ‘faithfulness’ 23 times, as in “great is Your faithfulness” (Lamentations 3:23). Once it is ‘steady’: Moses’ hands “remained steady until the sun went down” (Exodus 17:12). It is ‘faith’ only here:

Word by word
וְצַדִּיקבֶּאֱמוּנָתוֹיִחְיֶה
and · the righteousby · faithfulness · hishe shall live
Original form
בֶּאֱמוּנָתוֹ
be’emunato

What this tells us

Habakkuk is a prophet who argues with God. He opens with “How long, O LORD, must I call for help but You do not hear” (Habakkuk 1:2). Then he waits for an answer: “I will stand at my guard post and station myself on the ramparts” (Habakkuk 2:1). The LORD tells him to write the vision down and wait: “Though it lingers, wait for it, since it will surely come and will not delay” (Habakkuk 2:3). The word for “faith” is emunah: firmness, steadiness, faithfulness. It is a word for someone you can rely on. While the answer lingers, the righteous person lives by it: staying steady, holding on, the way Moses’ hands were held steady until sunset in the battle of Exodus 17. Habakkuk ends his book living out this line. Everything fails, “Though the fig tree does not bud and no fruit is on the vines”, and still he says, “yet I will exult in the LORD; I will rejoice in the God of my salvation!” (Habakkuk 3:17–18). Paul takes the line up in Romans: “The righteous will live by faith” (Romans 1:17). Some readers hear it mostly as trusting God, others as staying faithful to him; the Hebrew word holds both. Faith here is not having all the answers. It is staying steady while you wait for them, and being someone God can rely on in the meantime.

Read every verse in the original Hebrew and Greek, in the app

Tap any word to see its meaning, lexicon entry, and every other place it appears.

Download on the App Store
Romans 4:20–21
BSB
Yet he did not waver through disbelief in the promise of God, but was strengthened in his faith and gave glory to God, being fully persuaded that God was able to do what He had promised.

What the original says

πληροφορέω
plērophoreō (play-ro-for-EH-oh)
Strong's G4135

Behind the words “fully persuaded” in this verse is the Greek word plērophoreō (said play-ro-for-EH-oh).

Strong’s traces it to two words, ‘full’ and ‘to carry’. Here it means to be completely convinced.

This form, plērophorētheis, means ‘having been fully convinced’. It describes Abraham, and “fully” is part of the one Greek word.

It is a rare word in the Berean Standard Bible, 6 times: ‘persuaded’ here, and also ‘fulfilled’, in “the things that have been fulfilled among us” (Luke 1:1), and ‘fulfill’, in “fulfill your ministry” (2 Timothy 4:5):

Word by word
καὶπληροφορηθεὶςὅτιὃἐπήγγελταιδυνατόςἐστινκαὶποιῆσαι
andhaving been fully persuadedthatwhathe has promisedablehe isalsoto do
Original form
πληροφορηθεὶς
plērophorētheis

What this tells us

Paul is telling Abraham’s story to the church in Rome. Abraham did not pretend the facts were otherwise: “he acknowledged the decrepitness of his body (since he was about a hundred years old) and the lifelessness of Sarah’s womb” (Romans 4:19). By any human measure, the promise of a son was over. The words “fully persuaded” are one Greek word, plērophoreō: to be completely convinced, carried all the way. What Abraham was sure of was not his body but God: “that God was able to do what He had promised.” He “did not waver through disbelief”, and he “was strengthened in his faith and gave glory to God”. Notice the order. He looked at the facts honestly, and then looked past them to the promise. Hebrews says the same of Sarah: she conceived “because she considered Him faithful who had promised” (Hebrews 11:11). Think of walking out onto a frozen lake. Your confidence does not come from how light you are, but from how thick the ice is. Abraham’s faith was strong because it rested on something strong. You do not have to ignore what you see in order to trust God. The question this verse leaves is which convinces you more: the facts in front of you, or the One who made the promise.

Proverbs 3:5
BSB
Trust in the LORD with all your heart, and lean not on your own understanding;

What the original says

בָּטַח
batach (bah-TAKH)
Strong's H982

Behind the word “trust” in this verse is the Hebrew word batach (said bah-TAKH).

It means to trust: to feel safe and sure because of someone. The Hebrew word for “safety” in Psalm 4:8, betach, comes from it.

This form, betach, is a command: “trust”. It is the first word of the verse.

In the Berean Standard Bible, it is ‘trust’ 94 times, and also ‘secure’ and ‘rely’. A psalm uses it for the moment of fear: “When I am afraid, I put my trust in You” (Psalm 56:3):

Word by word
בְּטַחאֶליְהוָהבְּכָללִבֶּךָוְאֶלבִּינָתְךָאַלתִּשָּׁעֵן
trustinthe LORDwith · allheart · yourand · onunderstanding · yournotlean
Original form
בְּטַח
betach

What this tells us

Proverbs 3 is a father’s advice to his son: keep my teaching, and it will bring you long life and peace (Proverbs 3:1–2). In the middle of that advice come these lines, and right after them a warning: “Be not wise in your own eyes; fear the LORD and turn away from evil” (Proverbs 3:7). The word for “Trust” is batach: to feel safe because of someone, to lean on them and be secure. The verse sets two kinds of leaning side by side: “Trust in the LORD with all your heart, and lean not on your own understanding.” With all your heart means the whole of you, not a part kept back in reserve. The promise follows in the next verse: “in all your ways acknowledge Him, and He will make your paths straight” (Proverbs 3:6). A psalm says the same in a moment of fear: “When I am afraid, I put my trust in You” (Psalm 56:3). And Jeremiah: “blessed is the man who trusts in the LORD, whose confidence is in Him” (Jeremiah 17:7). Your understanding still matters; Proverbs is full of advice to use it well. The point is where you put your weight. Where are you leaning hardest on your own understanding right now? This verse invites you to rest that weight on the LORD instead.

Mark 9:24
BSB
Immediately the boy’s father cried out, “I do believe; help my unbelief!”

What the original says

πιστεύω
pisteuō (pis-TYOO-oh)
Strong's G4100

Behind the words “I do believe” in this verse is the Greek word pisteuō (said pis-TYOO-oh).

It is the action word that goes with pistis, the faith you met in Hebrews 11:1. It means to believe, to trust, to put faith in.

This form means ‘I believe’: the father says it of himself, right now. His next word, “unbelief”, is apistia, from the same family with ‘not’ in front. (The SBLGNT, the Greek text shown here, does not have ‘with tears’ or ‘Lord’, and neither does the Berean.)

In the Berean Standard Bible, it is ‘believe’ and its forms 219 times. It is also ‘entrust’: “Jesus did not entrust Himself to them” (John 2:24):

Word by word
Πιστεύωβοήθειμουτῇἀπιστίᾳ
I believehelpof metheunbelief
Original form
Πιστεύω
pisteuō

What this tells us

Jesus comes down from the mountain to find a crowd and an argument. A father has brought his son, who has a spirit that throws him “into the fire or into the water, trying to kill him” (Mark 9:22), and the disciples could not help. The father says, “But if You can do anything, have compassion on us and help us.” Jesus answers, “If You can?” and then, “All things are possible to him who believes!” (Mark 9:23). The father’s reply uses the word pisteuō: to believe, to trust. He says it and its opposite in one breath: “I do believe; help my unbelief!” He does not wait until his doubts are gone. He brings both to Jesus. Jesus does not send him away to come back with more faith. The boy is freed, and “Jesus took him by the hand and helped him to his feet, and he stood up” (Mark 9:27). The apostles once prayed a prayer of the same kind: “Increase our faith!” (Luke 17:5). Faith in this story is less like a full tank and more like a hand held out, even a shaking one. If your faith feels mixed with doubt, this father’s prayer is in the Bible for you. You can pray it word for word.

Romans 10:17
BSB
Consequently, faith comes by hearing, and hearing by the word of Christ.

What the original says

ἀκοή
akoē (ah-ko-AY)
Strong's G189

Behind the word “hearing” in this verse is the Greek word akoē (said ah-ko-AY).

It means hearing: the act of hearing, and also what is heard, a message or a report.

Here the form akoēs means ‘from hearing’: word for word, ‘faith from hearing’. The Berean, like the SBLGNT, reads “the word of Christ”.

In the Berean Standard Bible, it is ‘hearing’ or ‘hear’ 11 times, and also ‘news’: “News about Him spread all over Syria” (Matthew 4:24). One verse earlier it is ‘message’: “Lord, who has believed our message?” (Romans 10:16):

Word by word
ἄραἡπίστιςἐξἀκοῆςἡδὲἀκοὴδιὰῥήματοςΧριστοῦ
so thenthefaithfromhearingtheandhearingthroughwordof Christ
Original form
ἀκοῆς
akoēs

What this tells us

Paul has been asking how anyone comes to faith: “how can they believe in the One of whom they have not heard? And how can they hear without someone to preach?” (Romans 10:14). Then he quotes Isaiah’s sad question: “Lord, who has believed our message?” (Romans 10:16). The word for “hearing” is akoē: the act of hearing, and also what is heard, a message. Paul links the two in one line: “faith comes by hearing, and hearing by the word of Christ.” Faith does not start inside you as a feeling you have to produce. It starts with a message that comes to you from outside. John says the same about his own Gospel: it was written “so that you may believe that Jesus is the Christ, the Son of God” (John 20:31). Paul asks the Galatians whether they received the Spirit “by works of the law, or by hearing with faith?” (Galatians 3:2). Think of how you come to trust a friend: by listening to them, over time. Faith grows the same way. If your faith feels weak, this verse points somewhere simple: keep listening to the word of Christ. Faith comes from what you hear.

Behind "faith" are 12 different words

Your English Bible says "faith" 255 times. Behind it stand several Hebrew and Greek words:

πίστις
pistis
Strong's G4102
232 times: Hebrews 11:1
אָמַן
aman
Strong's H539
1 times: Genesis 15:6
אֱמוּנָה
emunah
Strong's H530
1 times: Habakkuk 2:4
πιστεύω
pisteuō
Strong's G4100
1 times: Mark 9:24
Also behind 'faith': bagad (H898, 7 times), oligopistos (G3640, 5 times), maal (H4603, 2 times), maal (H4604, 2 times), oligopistia (G6066, 1 time), apisteō (G569, 1 time), apistia (G570, 1 time), pistos (G4103, 1 time).
In the whole Old Testament the Berean says ‘faith’ only 13 times, 11 of them as ‘broke faith’ or ‘breach of faith’, being unfaithful. As trust, only twice: Habakkuk 2:4 and Isaiah 7:9. And the verb: English has no verb ‘to faith’, so the Berean says ‘believe’. Pisteuō is ‘believe’ 219× and aman 34×.
Source: Berean Standard Bible (tied word by word, DeepWord interlinear)

Reflect

Read it as yours

Mark 9:24 is a prayer anyone can pray, on a strong day or a weak one. Read it slowly, as your own:

“I do believe; help my unbelief!”

Name it

Where is it hardest for you to trust God right now? Proverbs 3:5 says “Trust in the LORD with all your heart.” Tell him plainly.

A prayer
LORD, I do believe; help my unbelief. I want to trust you with all my heart, and not lean on my own understanding. Make me fully persuaded that you are able to do what you have promised.

Carry with you

What has God promised that you find hard to be “fully persuaded” of?

Explore more in the app

One-time purchase. No subscription. No account.

Download on the App Store
DeepWord · Get the app App Store