en_tn/2jn/01/06.md

This is the commandment, just as you heard from the beginning, that you should walk in it

Conducting our lives according to God's commands is spoken of as if we were walking in them. The word "it" refers to love. "And he has commanded you, since you first believed, to love one another" (See: rc://en/ta/man/jit/figs-metaphor)