The teaching of the Letter to the Galatians is emphatic: “So then, as we have opportunity, let us do good to all, and especially to those who are of the household of faith” (6:10).
continued: Here Christians can see a dim prefigurement of the mystery of the Cross: so great is God's love for man that by becoming man he follows him even into death, and so reconciles justice and love.
Long awaited 2nd encyclical of the Holy Father. Complete here: http://www.vatican.va/holy_father/benedict_xvi/encyclicals/documents/hf_ben-xvi_enc_20071130_spe-salvi_en.html