Deuteronomy 15:1
At the end of every seven years thou shalt make a release. (Deuteronomy 15:1)
Every seven years.
 That is, in the seventh year, as in v. 12 (see Deut. 31:10; Jer. 34:14). The command of this verse is an extension of Ex. 21:2; Lev. 25:3.
Make a release.
 Literally, “thou shalt make a remission.” The word translated “release” means a temporary remitting, from the root “to let drop,” “to detach.” It is used in speaking of the land, “But the seventh year thou shalt let it rest,” that is, be released from cultivation and allowed to lie fallow (Ex. 23:11); and in referring to Jezebel’s being thrown down by her eunuchs (2 Kings 9:33). This “release” refers to a manumission from debt, from slavery, and also to a rest for the land from cultivation.