Definition of Faith in the New Testament
The Greek noun πίστις (pistis) appears throughout the New Testament as the primary term for faith, deriving from the verb πείθω (peithō), meaning "to persuade" [3, 4]. In the Septuagint, πίστις most commonly translates the Hebrew אֱמוּנָה (emunah), a term rooted in the concept of faithfulness and reliability [3, 4]. This etymological connection reveals that New Testament faith is not merely intellectual assent but involves trust grounded in the character of the one believed.
Lexical Range and Core Meaning
The word πίστις carries an active sense of "faith, belief, trust, confidence," consistently referring in the New Testament to religious faith directed toward God, Christ, or spiritual realities [3, 4]. Faith functions as "the persuasion of the mind that a certain statement is true," yet its primary idea is trust—a conviction that something is true and therefore worthy of reliance [1]. This trust admits of varying degrees, ranging from initial belief to "full assurance of faith," depending on the evidence and teaching that undergirds it [1].
Knowledge forms an essential element in all faith and sometimes appears as nearly equivalent to it (John 10:38; 1 John 2:3), yet the two remain distinct: faith includes assent, an act of the will that moves beyond mere cognition [1]. Romans 10:14–17 emphasizes that faith arises from teaching, underscoring its rational foundation [1].
The Classic Definition
Hebrews 11:1 provides the most concentrated description: "Now faith is the assurance of things hoped for, the conviction of things not seen" [2]. This verse does not offer a comprehensive definition but highlights faith's function in relation to perseverance—it "substantiates promises of God which we hope for, as future in fulfilment, making them" present realities [6]. The Greek term translated "assurance" (ὑπόστασις) conveys the idea of substance or foundation, while "conviction" (ἔλεγχος) denotes proof or evidence of unseen realities [6].
Faith as Active Reality
New Testament usage consistently portrays faith as dynamic rather than static. The "work of faith" in 1 Thessalonians 1:3 refers to "the working reality of your faith; its alacrity in receiving the truth, and in evincing itself by its fruits"—not mere intellectual assent but "a realizing, working faith" that manifests in continuous action [5]. This active dimension appears throughout the Pauline corpus, where faith in Christ (πίστις Χριστοῦ) functions as the means of justification and the governing principle of Christian life (Romans 3:22; Galatians 2:16) [4].
Sources
- Easton's Bible Dictionary “Easton's Bible Dictionary: Faith — Faith is in general the persuasion of the mind that a certain statement is true (Phil. 1:27; 2 Thess. 2:13). Its primary idea is trust. A thing is true, and therefore worthy of trust. It admits of many degrees up to full assurance of faith, in accordance with the evidence on which it rests. Faith is the result of teaching (Rom. 10:14-17). Knowledge is an essential element in all faith, and is sometimes spoken of as an equivalent to faith (John 10:38; 1 John 2:3). Yet the two are distinguished in this respect, that faith includes in it assent, which is an act ”
- Hebrews “Hebrews 11:1 (NASB) — Now faith is the assurance of things hoped for, the conviction of things not seen.”
- STEPBible TBESG “[G4102] G4102H = a Meaning of (G4102G) — <b>πίστις</b>, -εως, ἡ <BR /> (πείθω), [in LXX chiefly for אֱמוּנָה ;] <BR /> __1. in active sense, <b>faith, belief, trust, confidence</b>, in NT always of religious faith in God or Christ or spiritual things: <ref='Mat.8.10'>Mat.8:10</ref>, <ref='Luk.5.20'>Luk.5:20</ref>, <ref='Act.14.9'>Act.14:9</ref>, <ref='Rom.1.8'>Rom.1:8</ref>, <ref='1Co.2.5'>1Co.2:5</ref>, <ref='2Co.1.24'>2Co.1:24</ref>, <ref='1Ti.1.5'>1Ti.1:5</ref>, al.; with genitive obj., <ref='Mrk.11.22'>Mrk.11:22</ref>, <ref='Act.3.16'>Act.3:16</ref>, <ref='Rom.3.22'>Rom.3:22</ref>, <ref='G”
- STEPBible TBESG “[G4102] G4102G = (G4102G) — <b>πίστις</b>, -εως, ἡ <BR /> (πείθω), [in LXX chiefly for אֱמוּנָה ;] <BR /> __1. in active sense, <b>faith, belief, trust, confidence</b>, in NT always of religious faith in God or Christ or spiritual things: <ref='Mat.8.10'>Mat.8:10</ref>, <ref='Luk.5.20'>Luk.5:20</ref>, <ref='Act.14.9'>Act.14:9</ref>, <ref='Rom.1.8'>Rom.1:8</ref>, <ref='1Co.2.5'>1Co.2:5</ref>, <ref='2Co.1.24'>2Co.1:24</ref>, <ref='1Ti.1.5'>1Ti.1:5</ref>, al.; with genitive obj., <ref='Mrk.11.22'>Mrk.11:22</ref>, <ref='Act.3.16'>Act.3:16</ref>, <ref='Rom.3.22'>Rom.3:22</ref>, <ref='Gal.2.16'>Gal.”
- 1 Thessalonians (Presbyterian) “Jamieson, Fausset & Brown on 1 Thessalonians 1:3: work of faith--the working reality of your faith; its alacrity in receiving the truth, and in evincing itself by its fruits. Not an otiose assent; but a realizing, working faith; not "in word only," but in one continuous chain of "work" (singular, not plural, works), Th1 1:5-10; Jam 2:22. So "the work of faith" in Th2 1:11 implies its perfect development (compare Jam 1:4). The other governing substantives similarly mark respectively the characteristic manifestation of the grace which follows each in the genitive. Faith, love, and hope, are the ”
- Hebrews (Presbyterian) “Jamieson, Fausset & Brown on Hebrews 11 (introduction): DEFINITION OF THE FAITH JUST SPOKEN OF (Heb 10:39): EXAMPLES FROM THE OLD COVENANT FOR OUR PERSEVERANCE IN FAITH. (Heb. 11:1-40) Description of the great things which faith (in its widest sense: not here restricted to faith in the Gospel sense) does for us. Not a full definition of faith in its whole nature, but a description of its great characteristics in relation to the subject of Paul's exhortation here, namely, to perseverance. substance, &c.--It substantiates promises of God which we hope for, as future in fulfilment, making them”