From this particular command he passes to what is more general, requiring in all things a strict and unanimous adherence to the pure and primitive doctrine of the gospel, which would be the best expression of love to God, and the true centre and bond of love to one another, as 1 John 5:1,3.
Related Commentaries of 2 John 1:6
2 John 1:6
6 And this is love, that we walk after his commandments. This is the commandment, That, as ye have heard from the beginning, ye should walk in it.