Towards the end of Leviticus, after the well known sections about sins and sacrifice, and clean and unclean things, there is a section of the Law of Moses instructing Israel to be different from the nations around them, to not be like the pagans.
In Leviticus 25, this themes is developed in regard to Israel and slavery:
Lev. 25:39-55 “And if a countryman of yours becomes so poor with regard to you that he sells himself to you, you shall not subject him to a slave’s service.
40 ‘He shall be with you as a hired man, as if he were a sojourner; he shall serve with you until the year of jubilee.
55 ‘For the sons of Israel are My servants; they are My servants[slaves] whom I brought out from the land of Egypt. I am the LORD your God.”
No one in Israel was to make another Israelite their slave. They could be-come an indentured servant, a dependent servant, for a time. Foreigners and sojourners could fall into permanent slavery, but not those of Israel. The twice stated reason (vss. 42 and 55) is that God had already brought Israel out of slavery and they were His slaves/servants already.
This same truth, that God’s people are His own slaves is taught in the New Testament. (Ref. 1 Cor. 6:20, Rom. 6:18). This is the reason that Christians were not to become slaves. Just like Israel, we belong wholly to God. We cannot belong to another.
1 Cor. 7:23“You were bought with a price; do not become slaves of men.”