What is Christianity all about?

In our relationship with God we are to give him his legal right—namely, all that we have and are. The Christian is to be as a matter of course totally dedicated to God (Rom 12: 1–2) and filled with the Holy Spirit (Eph 5: 18). For his part God gives to us positionally, as we are in Christ, forgiveness of sins (Eph 1: 7), eternal life (Rom 6: 23), adoption as sons (Gal 4: 5), and the availability of unlimited help and power (Eph 1: 18–19).

Think of how much that means! Moreover, he gives to us experientially, as we are Spirit-filled, the fruit of the Spirit: love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control (Gal 5: 22–23). When this relationship is intact, the product in our lives will be righteousness (Rom 6: 16), and the by-product of righteousness is happiness. Happiness is an elusive thing and will never be found when pursued directly; but it springs into being as one pursues the knowledge of God and his righteousness is realized in us.

The other relationship is our relationship with our fellow men. This is governed by the second great commandment, as Paul explains: “The commandments, ‘You shall not commit adultery, You shall not kill, You shall not steal, You shall not covet,’ and any other commandment, are summed up in this sentence, ‘You shall love your neighbor as yourself’ ” (Rom 13: 9). Why is love the great commandment? Simply because all the other commandments are the outworking of love in practice (Rom 13: 10).

When we love others, we simply show that we have understood God’s love for us, and it is being worked out in our lives toward others. As John says, “If God so loved us, we also ought to love one another” (1 John 4: 11). What does love involve? To begin with, it means possessing the characteristics of love described in 1 Corinthians 13. Can we say, “I am patient and kind, I am not jealous or boastful, arrogant or rude; I am not selfish or irritable or resentful; I am not happy about wrong, but I rejoice in the right; I bear all things, believe all things, hope all things, endure all things”? Moreover, love will involve having a servant’s heart, a willingness to count others better than yourself and to serve and look out for their interests as well as your own (Gal 5: 13b–14; Phil 2: 3). Certainly Jesus himself is our supreme model here: think of how he stooped to wash his disciples’ dirty feet!

What will be the result when these two relationships are strong and close? There will be a unity and warmth among Christians. There will be a love that pervades the body of Christ; as Paul describes it, “speaking the truth in love, we are to grow up in every way into him who is the head, into Christ, from whom the whole body, joined and knit together by every joint with which it is supplied, when each part is working properly, makes bodily growth and upbuilds itself in love” (Eph 4: 15–16).

And what will be the result of this unity through love? Jesus himself gives us the answer in his prayer for the church: “that they may all be one; even as Thou, Father art in me, and I in Thee, that they also may be in Us; that the world may believe that Thou didst send Me … I in them, and Thou in Me, that they may be perfected in unity, that the world may know that Thou didst send Me and didst love them, even as Thou didst love Me” (John 17: 21–23). According to Jesus, our love is a sign to all people that we are his disciples (John 13: 35); but even more than that, our love and unity are living proof to the world that God the Father has sent his Son Jesus Christ and that the Father loves people even as he loves Jesus. When people see this—our love for one another and our unity through love—then they will in turn be drawn by this to Christ and will respond to the gospel’s offer of salvation. More often than not, it is what you are rather than what you say that will bring an unbeliever to Christ.

Craig, W. L. (1994). Reasonable faith : Christian truth and apologetics (Rev. ed., pp. 300–302). Wheaton, Ill.: Crossway Books.