πίστεως. (pisteos) in Romans 3:27: Noun Genitive Singular Feminine

Noun: this form names faith, trust, or belief as a concrete idea or reality in the sentence.

Genitive: this form usually marks a relationship, and here it links the noun to the preceding expression in a way that the context must define.

Singular: the form is grammatically singular here, presenting faith as one shared concept rather than multiple items.

Feminine: this noun is feminine in grammatical gender, which is a language feature and does not by itself make a theological or personal gender claim.

It follows διὰ νόμου and completes the phrase διὰ νόμου πίστεως.

The preposition διὰ with the genitive governs the phrase and presents the means or basis in a compact way.

In this verse, the genitive helps express a relationship within the phrase, most naturally reading as a law characterized by faith or a law associated with faith, depending on the larger flow of thought.

It does not by itself identify a different lemma, and it does not force a full doctrinal conclusion apart from the sentence.

High: The genitive faith phrase helps contrast boasting, works, and faith in Paul's argument.

Genitive noun completing the phrase law of faith. characterizes the law or principle in view as related to faith rather than works. Attached to nomou in the phrase law of faith. Governed by the prepositional phrase introduced by dia. The phrase is compact, so the immediate contrast with works controls how specific the explanation should be.

What kind of law or principle is being contrasted with works? The genitive links the phrase to faith, helping the reader hear the contrast without turning it into a separate code.

Supporting: The form supports law of faith or an equivalent relational rendering, but the context decides the explanatory gloss.

The phrase can be explained as faith-related without overdefining whether law means principle, rule, or another nuance. The genitive marks relationship, not a full doctrinal slogan by itself.

Law of faith is treated as a technical system proven by grammar alone: The form supports a faith relation; the verse's contrast with works and boasting controls the claim.

The witness reads πίστεως in Romans 3:27 within the clause ἀλλὰ διὰ νόμου πίστεως, so the form stands in a prepositional phrase after the contrast with works.

The lemma is πίστις, meaning faith, belief, or trust, and the form here keeps that lexical sense while placing it in a genitive relation.

Because the form is genitive after διὰ, it describes a relationship rather than standing as the main subject or action. The exact nuance is best taken from the contrast in the verse, not from the case alone.

The verse says boasting is excluded and then denies a works-based principle, replacing it with a faith-related one. The form supports that contrast without making the phrase more specific than the context allows.

This fits Paul's wider argument in Romans that righteousness is not grounded in human boasting or works, but is received through faith.

For readers and teachers, the form helps signal that faith is part of the sentence's governing contrast, so the verse speaks about the basis of boasting and justification rather than about faith as a detached topic.

Do not derive from the case alone that the phrase means a technical slogan, a separate law code, or a full doctrinal summary without the immediate argument.