What is the sum of the six commandments which contain our duty to man?

The sum of the six commandments which contain our duty to man is, to love our neighbor as ourselves,[1] and to do to others what we would have them to do to us.[2]

1. Matt. 22:39

   And a second is like it: You shall love your neighbor as yourself.

2. Matt. 7:12

   So whatever you wish that others would do to you, do also to them, for this is the Law and the Prophets.

Question 122, Westminster Larger Catechism