Πέτρου (Petrou) in John 1:40: Noun Genitive Singular Masculine
Πέτρου (Petrou) in John 1:40
Textual Witness
The witness reads Πέτρου in John 1:40, within the phrase ὁ ἀδελφὸς Σίμωνος Πέτρου.
How The Form Affects Interpretation
The form narrows the reference by identifying Simon as Peter and clarifying Andrew's family relation.
How To Communicate It
In communication, this genitive supports the simple identifying phrase brother of Simon Peter.
What Not To Say
- Grammatical form should serve context, not override it.
- Genitive case can suggest relationship, but the exact nuance must be read from the phrase and verse.
- Masculine grammatical gender describes the noun's class and should not be turned into a theological gender claim.
What Does The Label Mean?
Noun: this form names a person, here the name Peter, and functions as a normal substantive in the sentence.
Genitive: the form usually marks relationship, association, source, or description, and here it identifies Peter in relation to Simon.
Singular: the form is grammatically singular in this occurrence, referring to one individual rather than a group.
Masculine: the noun belongs to the masculine grammatical class, which describes its form and does not itself make a theological claim.
What The Form Does In This Verse
Σίμωνος Πέτρου in the phrase ὁ ἀδελφὸς Σίμωνος Πέτρου
The genitive naming chain depends on ἀδελφὸς and identifies Andrew by relation to Simon Peter.
It helps specify which Simon is meant, so the phrase reads naturally as Andrew, the brother of Simon Peter.
It does not mean Simon belongs to Peter, and it does not make Peter the subject of the sentence.
How Much The Form Matters Here
Moderate: The genitive proper name helps identify Andrew by his family relation to Simon Peter.
Genitive proper name in an identifying family phrase. helps specify Simon as Peter in the phrase brother of Simon Peter. Attached to Σίμωνος Πέτρου. Governed by the brother phrase identifying Andrew. The form clarifies identity and family relation; it does not create a separate theological claim.
Which Simon is Andrew related to? The genitive naming phrase identifies him as Simon Peter.
Direct: The form supports the natural phrase brother of Simon Peter.
The phrase identifies Simon Peter, not a relation of Simon belonging to Peter. The genitive proper name helps with identification, not doctrine.
Genitive chain is assigned the wrong relationship: The phrase identifies Andrew as brother of Simon Peter; context controls the relationship.
How The Interpretation Is Derived
The witness reads Πέτρου in John 1:40, within the phrase ὁ ἀδελφὸς Σίμωνος Πέτρου.
The lemma is Πέτρος, the personal name Peter, so the form keeps that identity while inflecting for genitive case.
In this clause, the genitive naming chain describes Andrew as the brother of Simon Peter, using Peter to identify which Simon is meant.
The verse presents Andrew as one of the two who heard John and followed Jesus, while the genitive phrase identifies him by his family relation to Simon Peter.
Elsewhere Peter is a major apostolic figure, and here the grammar simply lets the narrative identify him without adding extra theological weight.
For readers and translators, the phrase should read naturally as brother of Simon Peter, preserving the family relation without overexplaining the case form.
Do not derive a special theology from the case ending, and do not read the genitive chain as if Simon belonged to Peter.