There has been a lot of fabulous work done on Old Testament laws that protect immigrants. I would highly recommend you check out Daniel Carroll's book Christians at the Border and Matt Soerens and Jenny Hwang's Welcoming the Stranger.
Without repeating their excellent work, I want to point out one idea when it comes to immigration.
God desires that immigrants be treated justly.
Our temptation, when it comes to justice, is to define justice as "behavior within the law." To treat immigrants with justice, then, may look like protecting them from abuse and arresting them if their documents are out of line.
But the justice of God doesn't assume the law. At least, the justice of God doesn't assume the human law.
When God formed and re-formed and re-re-formed his people, he gave them a new set of laws. The laws God gave his people looked a lot like the laws they already had, the laws of the surrounding culture. Moses has a lot in common with Hammurabi. Paul has a lot in common with Philo. But the law of God always pushed the edges of the law.
Jesus was famous for this.
In his teaching on divorce, he shifted the conversation from "when can a man divorce his wife?" to "when must a man divorce his wife?" In his teaching on neighborliness, he shift the conversation from "to whom must I prove neighbor?" to "to whom can I prove neighbor?"
We can see God's values from his law. When Jesus teaches on the law, he always pushes people to consider the heart and the Person behind it.
This comes through with blinding clarity in Jesus' teaching in Matthew 25:31-46. Jesus teaches that a long list of kind and generous deeds, done for a certain set of people, will be considered as though they had been done for him. See how deeply he identifies with these people. These deeds are done for him. Even if the doers don't realize it.
This principle of identification, which I wrote about yesterday, lies behind and beneath, as a foundation for Jesus' ethic of generosity. Jesus doesn't just tell people to be generous. He tells them why. Be generous to these people because I so closely identify with them that everything you do for them will be, in some mysterious way, done for me.
What does this have to do with immigration?
Buried in the center of this list in Matthew 25 is this phrase: "I was a stranger and you invited me in."
The word "stranger" reverberates back through the Old Testament. In Genesis 15 God's people are called out to be strangers. This is re-affirmed later in Leviticus 25 as they are reminded that they live in the land as strangers. And a few breaths later they are called to help their fellow-strangers.
But the Why behind all this lay obscured in shadow until the right time. When God revealed himself in Christ, the reason behind his legal command for justice for immigrants finally became clear.
This is the seventh post in a Short Series: A Biblical Perspective on Immigration. The next post in this series will be ... The Immigrant Church.