The central content of the preaching of the gospel is the person of Jesus Christ. The Christian faith differs fundamentally in this respect from all other historical religions. While these also have important founding figures, such as Buddha or Muhammed, whom they base their authority upon, none of these founders is comparable in importance to the place given to Jesus Christ in Christianity. The most basic requirement of evangelistic preaching is therefore to clearly understand and explain the person and work of Jesus Christ. The New Testament gives clear answers why Jesus is God's Son and the savior of the world. The result of this is the complete and ultimate claim to truth with regard to his person. In an age of globalization, ideological relativism and religious pluralism, evangelism must struggle to boldly and clearly proclaim these biblical/theological basics.
Let me give the most important reasons from scripture to prove that Jesus Christ is the only Son of God. These arguments should be shared and proclaimed in the process of dialogue with people of other religious beliefs to give them the chance to understand the biblical message concerning Jesus Christ.
1. Jesus Teaches with Divine Authority
Just as Moses received the law on Mount Sinai, so Jesus ascended the mountain where he spoke the beatitudes in order to proclaim the new law of the Kingdom of God (Matthew 5). The authority of Jesus to proclaim the will of God is also evident in his position on the Sabbath, which was provocative to Judaism: “For the Son of Man is Lord of the Sabbath” (Matthew 12:8).
2. Jesus Has the Right to Bind People to His Person
Because Jesus, the Son of God, is so unique, the eternal destiny of every human being depends on his or her relationship to Jesus Christ (Luke 12:8). Each person to whom the death of the Lord is proclaimed in a way that he or she can understand in his or her context and can accept a personal relationship with Jesus, is responsible before Christ in a final eschatological sense. For all who have had no personal confrontation with Christ through the preaching of the gospel, the criteria in the final judgment is demonstrated in Matthew 25:40: “I tell you the truth, whatever you did for one of the least of these brothers of mine, you did for me.’“
By reason of the uniqueness and finality of Christ, it is therefore valid and binding on us here and now that Jesus had the divine authority to bind people to himself and to call them to follow him. This power to bind other people to his own person exclusively belongs to the Son of God. Whenever a person tries to usurp this divine right and take it away for him or herself, it will always result in a catastrophe. In Germany, we experienced this in the 1930s when Hitler required every soldier to swear an oath of allegiance to his person instead of any constitution or other objective authority; he thereby bound them absolutely to himself. Binding a person entirely to oneself and making a covenant of an absolute loyalty of faith and obedience are rights reserved only for God the Father and for the one he sent, Jesus Christ.
3. Jesus as Creator Shares God’s Creative Power over Nature
The confession that Jesus is the Son of God means that he belongs to the side of the creator, not to that of created beings. As creator, he has unlimited authority over all powers and forces of nature. The unique, creative power of Jesus is also shown in that he can make something from nothing. This is evident in a most exemplary way in the feeding of the five thousand.
4. Jesus Has the Unique Right to Forgive Sins
In Mark 2:1-12, the story is told of how the people pushed their way into the house where Jesus was preaching. Wanting to help their lame friend, four men got up onto the flat roof of the house. They opened the roof and lowered the lame man directly to Jesus' feet. Jesus looked at the man and simply said, “Son, your sins are forgiven” (2:5). The scribes and teachers of the law are more than irritated by this remark. The authority to forgive sins is a right belonging exclusively to God's sovereignty, because the forgiveness of sins is, in a way, a creative act in the reverse direction.
The most basic requirement of evangelistic preaching is to clearly understand and explain the person and work of Jesus Christ.
At the creation, God called into existence what did not previously exist. Human beings can only change the form of material which already exists; they cannot produce and bring into being anything fundamentally new. Corresponding to this is the matter of forgiveness of sins. Sin is produced by fallen humanity. The blood of Abel cries out from the earth to God, and Cain cannot change this. Forgiveness is a sovereign act of God in which he speaks out of existence that which exists. This is precisely what Jesus did when he said: “Son, your sins are forgiven.” Moreover, in order to confirm this unique authority, he added: “Which is easier to say to the paralytic, 'Your sins are forgiven,' or to say, 'Get up, take you mat and walk?’ But that you may know that the Son of Man has authority on earth to forgive sins . . .” He said to the paralytic, “I tell you, get up, take your mat and go home” (2:9-11). Through the power of Jesus as creator, he proves publicly the yet greater power to forgive sins. Jesus has this power because he is both priest and sacrifice at the same time. Being sinless, he was made to be sin by God. He carried the consequence of sin and death in order to grasp people from the power of sin and death.
5. Jesus’ Power over Death
Last we come to the most profound and all-encompassing confirmation of the divine omnipotence and completeness of Jesus, namely, the resurrection.
One of the strangest statements in all of the New Testament is found in 1 Corinthians 11:26: “For whenever you eat this bread and drink this cup, you proclaim the Lord's death until he comes.” This challenge to proclaim the Lord's death is quite odd. At best, one can commend the outstanding deeds of a dead person performed during his or her lifetime (i.e., he or she was a great inventor, a brilliant musician, an outstanding politician or a pioneering discoverer). In certain cases, one could even praise the courageous, yet composed, death of a person such as Socrates. But death as death itself one cannot make as the substance of one's proclamation.
Yet, the mystery of the divine Sonship of Jesus which is revealed in the cross and in the resurrection as victory over sin and death is different. Holy God and sin are absolute opposites. The living God and death are radical opposites. In the Old Testament, one can recognize this because every priest who touched a dead body became ritually unclean. Then, on Golgatha, the unimaginable occurred: The one who himself is God was made to be sin by God. Holy God identified himself with sin on the cross of Christ. Judgment against the world took place. Moreover, in this judgment the power of sin was not only conquered, it was also destroyed. The living God identified himself with death and annihilated the power of death. One death devoured another and won the victory. Satan was destroyed.
Therefore, we should proclaim the death of the Lord because his death does not mean destruction, but redemption from the power of sin and a beginning of a new creation through the resurrection of the dead. People who have accomplished much in their earthly lives have, at best, improved somewhat the conditions of earthly life under the conditions of sin and death. The Son of God is, therefore, the only and unique savior of the world and the completion of God's plan of salvation and his revelation of himself. We must focus our eyes on Colossians 1:15-20:
“He is the image of the invisible God, the firstborn over all creation. For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. He is before all things, and in him all things hold together. And he is the head of the body, the Church; he is the beginning and the firstborn from among the dead, so that in everything he might have the supremacy. For God was pleased to have all his fullness dwell in him, and through him to reconcile to himself all things, whether things on earth or things in heaven, by making peace through his blood, shed on the cross.”