Jesus tells us that it's not enough to love those who love us. We must love even our enemies (Matthew 5:43-48,) every human being in the world. That includes immigrants and refugees. This is not just a political issue. It is a serious moral issue. Jesus tells us that we will even be judged on whether we welcomed the homeless.
Through the prophet Isaiah (58:7-10) God tells us, "Shelter the oppressed and the homeless, clothe the naked when you see them....If you remove from your midst oppression, false accusation and malicious speech, if you deprive yourself for the hungry and satisfy the needs of the afflicted, then your light will rise in the darkness and your darkest hour will be like noon."