He said, “I will certainly return to you when the season comes round. Behold, Sarah your wife will have a son.” Sarah heard in the tent door, which was behind him.
⛓ Read Genesis 18 forward — the whole chapter and its afterlife →Where this passage surfaces again, sorted by the strength of the link. Each kind of reuse — formal quotation, deliberate allusion, faint echo, figural pattern — carries its own mark. Follow any reference to read it in place.
Quotation1
A formal citation — high verbal volume, often introduced by a saying-formula.
v.9 'At the appointed time I will come, and Sarah will have a son' explicitly named 'a word of promise.' Conflates the LXX of Genesis 18:10 ('I will return to you at this season') with the promise of a son; the miraculous, promise-born birth of Isaac grounds Paul's 'children of the promise' argument.
High confidenceAllusion1
A deliberate verbal borrowing without a citation formula.
The 'born through promise' language (v.23) echoes the annunciation 'I will surely return to you, and Sarah your wife shall have a son.' This is the verbal source of the divine promise of Isaac that Paul treats as paradigmatic; recurrence with 17:16 strengthens it.
Medium confidence