Jeremiah 34:8

We have here another prophecy upon a particular occasion, the history of which we must take notice of, as necessary to give light to the prophecy. I. When Jerusalem was closely besieged by the Chaldean army the princes and people agreed upon a reformation in one instance, and that was concerning their servants. 1. The law of God was very express, that those of their own nation should not be held in servitude above seven years, but, after they had served one apprenticeship, they should be discharged and have their liberty; yea, though they had sold themselves into servitude for the payment of their debts, or though they were sold by the judges for the punishment of their crimes. This difference was put between their brethren and strangers, that those of other nations taken in war, or bought with money, might be held in perpetual slavery, they and theirs; but their brethren must serve but for seven years at the longest. This God calls the covenant that he had made with them when he brought them out of the land of Egypt, Jer 34:13, Jer 34:14. This was the first of the judicial laws which God gave them (Exo 21:2), and there was good reason for this law. (1.) God had put honour upon that nation, and he would have them thus to preserve the honour of it themselves and to put a difference between it and other nations. (2.

— Matthew Henry's Concise Commentary (public domain)

By the law a Hebrew, after having been a bond-servant for six years, on the seventh was to be let go free (Exo 21:22; Deu 15:12). Zedekiah made a covenant--with solemn ceremonial in the temple (Jer 34:15, Jer 34:18-19). them--bond-servants (Jer 34:9).

— Jamieson-Fausset-Brown Commentary (public domain)