Doctrine and love are both needed

1. Assurance (vv. 19-20) - No Christian should treat sin lightly, but neither should he be harder on himself than God is. An “accusing conscience” robs a believer of peace. We need to be careful or the devil will accuse us and rob us of our confidence ( Rev. 12:10). His voice of assurance is stronger than the accusing voice of our own conscience.
2. Answered Prayer (vv. 21-22) - A believers’s relationship to other Christians cannot be divorced from his prayer life. These verses do not give us all the conditions for answered prayer, but they emphasize the importance of obedience. “And whatsoever we ask, we receive of Him, because we keep His commandments.” If we are truly seeking God’s will, there are some requests that we will not make.
3. Abiding (vv. 23-24) - Faith toward God and love toward man are the two basic ingredients of a Christian’s walk. It is easy to emphasize correct doctrine and neglect love for others.  However, some will tell you that doctrine is not important and that love is our main responsibility. The truth is that both doctrine and love are important.

John certainly emphasizes the two things which are well-pleasing in God’s sight, the two commandments on obedience to which our relationship to God depends. (1) We must believe in the name of his Son Jesus Christ.  (2) We must love one another, even as he gave us his commandment. This commandment is found in John 13:34 which says we must love each other with that same selfless, sacrificial, forgiving love with which Jesus Christ loved us.