in which he explains that the priority given to acquiring a Hebrew slave is meant to limit slavery
"When you acquire a Hebrew slave" – Should you wish to acquire a slave, acquire a Hebrew slave first. Do not say, I will acquire a slave whom I will have work for me forever, and not acquire one whom I will have to release after six years – for the brand of slavery on Israel is transitionary, not permanent, the reason being that they are the servants of the Almighty – and he shall be released by you on the seventh year.
Or HaHaim, Exodus, Mishpatim Reading Portion, p. 17, in Eshkol Press Mikra'ot Gedolot, Jerusalem, 1876
