Where does “Иуда” come from?

Иуда (Russian) comes from Ancient Greek Ἰούδας, from Hebrew יְהוּדָה — Judas; Judah, Judas.

Ancestry of “Иуда”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	Ἰούδας	—
2	Hebrew	יְהוּדָה	Judas; Judah, Judas

Иуда — Etymology, Origin & Word History | Etymology Explorer