In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother.

This shows who belongs to God and who belongs to the devil: those who don't do what is right aren't from God, and those who don't love their brothers aren't either.

King James Version

Simple English

* Work in progress - there may be occasional inaccuracies