John Gill Commentary Leviticus 25:44

"And as for thy bondmen, and thy bondmaids, whom thou shalt have; of the nations that are round about you, of them shall ye buy bondmen and bondmaids." — Leviticus 25:44 (ASV)

Both your bondmen, and your bondmaids, which you shall have ,
&c.] Such it seems were allowed them, if they had need of them; but if they had them, they were to be not of the nation of Israel, but of other nations.

This is an anticipation of an objection, as Jarchi observes; if so, who shall I have to minister to me? The answer follows, they [shall be] of the heathen that are round about thee, of them shall you
buy bondmen and bondmaids ;
that is, of the Ammonites, Moabites, Edomites, and Syrians, as Aben Ezra, that were their neighbours, that lived round about them, of any but the seven nations, which they were ordered utterly to destroy; wherefore Jarchi observes it is said, "that are round about thee"; not in the midst of the border of your land, for them they were not to save alive, (Deuteronomy 20:16) .