“Each of you took back his male and female slaves, whom you had set free” (v16). In the ancient world, poor people often sold themselves as laborers to pay off debts. God had warned the Israelites not to allow this practice to condemn people to a life of slavery; “owners” were commanded to set people free after 7 years. Under King Zedekiah, the Israelites had set people free, but apparently the owners didn’t like the economics of freedom and had re-enslaved their workers.
God didn’t let Israel hide behind what was “normal business” in their culture. He calls His people to be different, to honor Him by promoting justice for the poor, protecting the vulnerable, and proclaiming freedom (v8).