For the Israelites belong to me as servants

 Leviticus 25:29-55

Anyone who sells a house in a walled city retains the right of redemption a full year after its sale. During that time the seller may redeem it. If it is not redeemed before a full year has passed, the house in the walled city shall belong permanently to the buyer and the buyer’s descendants. It is not to be returned in the Jubilee.

The Levites always have the right to redeem their houses in the Levitical towns, which they possess.

But the pastureland belonging to their towns must not be sold; it is their permanent possession.

If any of your fellow Israelites become poor and are unable to support themselves among you, help them as you would a foreigner and stranger, so they can continue to live among you.

If any of your fellow Israelites become poor and sell themselves to you, do not make them work as slaves. They are to be treated as hired workers or temporary residents among you; they are to work for you until the Year of Jubilee.

Even if someone is not redeemed in any of these ways, they and their children are to be released in the Year of Jubilee, for the Israelites belong to me as servants. They are my servants, whom I brought out of Egypt. I am the Lord your God.

Why?
The people of Israelite are belong to the Lord as God's servants, so they could not be slaves or serve foreigner.

People sometime may become poor or mistreated in our society, each of us should have love on them to help them, treat them as hired worker, they are not slaves of ours.

For we are the member of God's children, God is love so we should have he image of Jesus Christ to love them.

How?

God is love and righteousness, so every Christian show walk on the way of God and obey his commands.