Luke 1:55
as he had spoken to our fathers, to Abraham, and to his seed.
Luke 1:72-73
to perform mercy towards our fathers, and to remember his own holy covenant:
Treasury of Scripture Knowledge
Summary
Wherefore it shall come to pass, if ye hearken to these judgments, and keep, and do them, that the LORD thy God shall keep unto thee the covenant and the mercy which he sware unto thy fathers: