1 John 3:23 23And this is his commandment, that we should believe in the name of his Son Jesus Christ and love one another, just as he has commanded us.
Jesus gave one commandment with two parts: believe and love. These two commands summarize Jesus’ teachings, especially as found in the Gospel of John. The referent for his command must refer to God because of the mention of his Son. Everything Jesus taught came from the Father (John 7:16–18; 8:26-29), so there is no difference between the sources. Jesus revealed what the Father’s will is: that everyone believe in Jesus as the Son (vertical relationship) and let that faith lead them to love one another (horizontal relationship). John has succinctly summarized the gospel message in his first three chapters.
To believe in the name is to believe the claims Jesus made about himself. Believing (pisteuō) as a verb is one of the keywords in John’s Gospel and the reason he wrote it (John 20:30-31) and is the Father’s will for humanity (6:40). The outcome of believing in Jesus is eternal life. Being born again or from above through the Holy Spirit ought to lead to a change of thinking and behavior, evidenced in love. Jesus expressly commanded his disciples to love one another (John 13:34; 15:12, 17).
These two parts are necessarily linked together. In order to love others, we must have faith in Jesus Christ. Likewise, we must believe in Jesus in order for love to flow through us. If we say we believe but do not love, our belief is invalidated. Love sourced in anything other than faith will deteriorate into selfishness and conditioned love. If we attempt to love people out of our own strength, we will often fail or become frustrated, because people are sometimes difficult to love. They will disappoint us, betray us, ignore us, and even abuse us. At best, we may even come to the point of merely tolerating being in their presence. The only way we can let love triumph in our daily lives is to put ourselves completely at the altar of consecration and commitment before Christ and say, “Here I am, use me as a channel of your love.” Holiness expressed as love results from the sanctification of life.