Where does “Яков” come from?

Яков (Russian) comes from Ancient Greek Ἰάκωβος, from Ancient Greek Ἰακώβ, from Hebrew יַעֲקֹב, from Hebrew עָקֵב — heel of the foot; heel.

Ancestry of “Яков”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	Ἰάκωβος	—
2	Ancient Greek	Ἰακώβ	—
3	Hebrew	יַעֲקֹב	Jacob
4	Hebrew	עָקֵב	heel of the foot; heel