A good motivation is what is needed: compassion without dogmatism, without complicated philosophy; just understanding that others are human brothers and sisters and respecting their human rights and dignities. That we humans can help each other is one of our unique human capacities.
If you have religious faith, very good, you can add on secular ethics, then religious belief, add on it, very good. But even those people who have no interest about religion, okay, it's not religion, but you can train through education.
Genuine happiness consists in those spiritual qualities of love, compassion, patience, tolerance and forgiveness and so on. For it is these which provide both for our happiness and others happiness.