The foundation for the sanctity of human life is not social agreement but theological fact: humans bear God's image. To take a human life is to strike against God's image-bearer. This is the deepest possible argument for human dignity.
Memory phrase: Every person bears God's image.
Talk about it: If everyone is made in God's image, how should that change the way we treat people who are different from us?
Prayer: God, help me to treat every person I meet as someone who bears Your image.