Yoreh Deah Siman 267 Seif 8

ח עֶבֶד שֶׁמָּלוֹ רַבּוֹ וְחָזַר לְגֵיוּתוֹ וּמְכָרוֹ לְעוֹבֵד כּוֹכָבִים, וְחָזַר יִשְׂרָאֵל וּקְנָאוֹ מִמֶּנּוּ, הֲרֵי הוּא כְּיִשְׂרָאֵל מוּמָר וְאֵינוֹ צָרִיךְ טְבִילָה אֶלָּא מַלְקוֹת.

 

Seif 8

 

A slave that was circumcised that rebels and becomes haughty and one sells him to idolaters, and then returns to the Jew who sold him, he is considered like an apostate Jew and their is no need to immerse him only lash him.