Exodus 21:2 limits Hebrew slavery to six years — contrasting with the permanent foreign slavery permitted here.

Deuteronomy 5:14 requires Sabbath rest for foreign slaves — a related law applying to those permitted here.

Isaiah 14:1 prophesies that sojourners will attach themselves to Israel — a future inclusion that contrasts with the permission here to buy them as slaves.

Isaiah 14:2 describes a future reversal where Israel takes slaves from their captors — relating to the permission here to buy foreign slaves.

Exodus 12:44 shows that bought foreign slaves could participate in Passover after circumcision — adding context to the rules about foreign slaves here.

Numbers 31:18 describes taking Midianite virgins as plunder — parallel to buying slaves from nations here.