Halakhah for Arakhin 57:31

And the commandment is practiced by males, but not by females - as a woman does not acquire a Hebrew slave (Bava Metzia 71a). And [this is] specifically when Israel is dwelling on its land - as so does the received explanation (Arakhin 29a) come [to tell us], that [the law of] a Hebrew slave is only practiced when the Jubilee is practiced. And it is explicit (Arakhin 32b) that the law of Jubilee is only in the Land. And one who transgresses it and does not do to the slave that which is written about him, negates a positive commandment, and also teaches his soul to be cruel. And it is almost as if he testifies about himself that he is not from the Children of Israel, since they are merciful ones [who are] the children of merciful ones (Shabbat 97a; Yevamot 79a).

From the laws of the commandment is that which they, may their memory be blessed, said (Avodah Zarah 65a) about that we do not give free presents to them, that [it is] specifically to one who worships idolatry, but not to one who does not worship idolatry - even though he remains a gentile to eat disgusting animals and creeping animals and all of the other sins like a resident alien. As since he has accepted the seven [Noachide] commandments, we support him and we give him free presents; and they may their memory be blessed, said (Arakhin 29a) that we only accept a resident alien at a time when the jubilee is practiced. And also that which they, may their memory be blessed, said (Gittin 61a) that it is permissible to support the poor of the gentiles with the poor of Israel because of the ways of peace. And the rest of its details - are elucidated in Tractate Avodah Zarah (see Tur, Yoreh Deah, 151).