v.7: command - love one another, see 2 John v.5
     new because of new example set by Jesus, see John 13:34 & Mark 12:29-31
v.9-11: Love - 1 Cor 13:4-8a, 'wanting God's best for someone else'
v.12-14: first "children" - in the sense all people are children (here, of God)
     second "children" - infants (could be spiritually)
v.13-14: fathers, young men & children - spiritually
v.15-17: James 4:4-5, can't love God's stuff & stuff not of God