I have been asked this question frequently by young people. Why God in the Old Testament appears powerful, angry, punishing, while He appears in the New Testament kind, loving, meek, and forgiving. Is He the same God in the Two Testaments? The answer is YES; the God of the New Testament is the same God of the Old Testament. But we must understand the relation between the Old and the New (covenants)Testaments.
In the Old Testament, God was concealed; no one could see Him “you are a God who has been hiding yourself. You are the God of Israel. You save us” (Isaiah 45:15). God was concealed, and nobody, even the prophets, saw him or heard his voice. In Exodus chapter thirty-five, Moses asked God “Now show me your glory”( Exodus 35:18); God answered, “No one can see me and stay alive” (Exodus 35:20). And in the Gospel of John (5:37), Jesus Himself said “The Father who sent me is himself a witness about me. You have never heard his voice. You have never seen what he really looks like.” So the prophets of the Old Testament had inspirations and guidance by the Holy Spirit but not an actual revelation of God. “The Holy Spirit guided the prophets as they spoke” ( 2Peter1:21). So those who defined God who was obscured in the Old Testament were the prophets who did not see God and who had not yet accepted the dwelling of the Holy Spirit because the Holy Spirit had not yet been given because Jesus was not yet glorified. “ Jesus stood up and spoke in a loud voice. He said, “let anyone thirsty come to me and drink. Does anyone believe in me? Then, just as scripture says, rivers of living water will flow from inside them. When he said this, he meant the Holy Spirit. Those who believed in Jesus would receive the spirit later. Up to that time, the spirit had not been given. This was because Jesus had not yet received glory” (John 7:37-39). Thus, the image reflected by the Old Testament’s prophets about God came in line with the limited possibilities of revelation in the Old Testament and their limited human ability to receive revelation, to express it, and to formulate it for the people. Thus we can understand why God's image was absurd in the Old Testament. It is the shortcomings of man, i.e, the prophet, that he could not conceive the true image of God and he had given us this image which was affected by the weakness of humanity and the fall of man under darkness and the shadow of death.
In the Gospel of John we read “No one has ever seen God; the only God, who is at the Father’s side, He (the Word), has made him known”( John1:18). St. John’s point is clear; that the God of the Old Testament had been revealed in the New Testament, and had taken on flesh who is Jesus Christ. Jesus Christ, the Word and the Wisdom of God, was incarnated to reveal for us the true image of God. “In the beginning was the Word, and the Word was God. All things were made through him and without him was not anything made that was made”( John 1:1-3). So the Revelation in the New Testament is not inspiration given to God’s prophets to tell people about God, but it is Jesus Himself the incarnated Word and Son of God. Jesus said, “But I know Him, I am from Him, and He sent me” (John 7:29). He is God revealed in the flesh. In the letter to the Hebrews chapter one, explains to us clearly the relation between the Old and the New Testament. “ Long ago God spoke many times in many ways to our ancestors through the prophets. And now in these final days, he has spoken to us through his Son. God promised everything to the Son as an inheritance, and through the Son he created the universe. The Son radiates God’s own glory and expresses the very character of God, and he sustains everything by the mighty power of his command” (Hebrews1:1-3). So Jesus came to our world to radiate God’s own glory and to express for us the very character of God.
What was written in the Old is that God loves His people, and He will save them. God did fulfill the promise of salvation in His Son Jesus Christ. God had sent His only begotten Son to save humanity from the sting and the power of death (i.e, sin) that entered man's life.“Sin entered the world because one man sinned. And death came because of sin. Everyone sinned, so death came to all people” (Romans 5:12). Jesus came to change man's sinful by giving him His holy and eternal life through the Holy Spirit. On the cross, He confronted sin and death and defeated them in His body which is our body. He was resurrected and gave His resurrection i.e, His overcoming power over death) to all who believe in Him, accept Him as Lord and Savior, and receive His power over the grip of sin in the Holy Spirit.
We Christians, after having the revelation of the New Testament, and the true image of God was revealed in His incarnated Son, now we know who God is. God is a lover; He is the source of life and being; He is the creator, giving birth to everything. The creator cannot be at the same time the destructor. In the book of Wisdom chapter one we read “Do not court death by your erring way of life, nor draw to yourselves destruction by the works of your hands. Because God did not make death, nor does He rejoice in the destruction of the living. For He fashioned all things that they might have being, and the creatures of the world are wholesome;”( wisdom 1:5). It is evident in this verse that God does not make death nor rejoice in the destruction of the living. In the New Testament, the Lord Himself told us that the devil is the enemy of man; he came to destroy and kill.“From the beginning, the devil was a murderer. He has never obeyed the truth. When he lies, he speaks his natural language. He does this because he is a liar. He is the father of lies” (John 8:44). So the one who destroys and kills is not God but the devil.
As Christians, we establish our faith in the person of Christ and the unity with Him. We read the Old Testament with the new eyes and new perspectives of the new revelation and not vice versa, as some do. They establish the understanding of the New Testament based on the Old, considering that the Old came first. This is a mistake because the Old was a message and a prophecy for the New hope coming to reveal God’s love to humanity and His salvation plan, which will restore man to his original image and likeness in which he was created.“And without controversy great is the mystery of godliness: God was manifested in the flesh, justified in the spirit, seen by angels, preached among the Gentiles, believed on in the world, received up in glory.” ( 1Timothy3:16).
In the old, the people of Sodom and Gomorrah were tempted by the devil cause they did not obey the word of God. They rejected God, their creator, the true and faithful God who provides protection, and they separated themselves from Him by sin, obeying the devil’s evil lusts. So when the murderer and the destructor came to destroy them, there was no protection. The Prophet of the Old Testament knew that those people were sinners and, according to the law, they should be punished, so he perceived that what happened to them was God’s punishment. In the New Testament, Jesus the Son of God, our Lord and Savior, told us that the devil is the destructor and killer of man; he tempts him and then accuses him and destroys him. So we understand now that what happened to Sodom and Gomorrah was the consequence of obeying the wicked evil one they followed.
In the second letter of Peter chapter one, we read,”for prophecy never came by the will of man, but holy men of God spoke as they were moved by the Holy Spirit" (2 Peter 1: 21). Some people generalize this verse to all the Old Testament book, but this generalization will cause us to deviate from the truth; because the Old Testament is not limited to prophecies alone, but it also includes history, heritage, and traditions of the Jewish people, wrong actions and attitudes of human beings who were under the power of sin, darkness, and the shadows of death and were waiting for the savior to come. “Through the tender mercy of our God, with which the Dayspring from on high has visited us; to give light to those who sit in darkness and the shadow of death...” (luke1:78-79). So, on the whole, the idea of revelation does not apply to all the books of the Old Testament, but it applies to God's commandments and prophecies only. We also learn many valuable and disciplinary lessons from the history and the events narrated in the Old Testament, which were undoubtedly an acurate picture of God’s care for His people.“God has breathed life into all scripture. It is profitable for doctrine, for reproof, for correction, for instruction in righteousness...” ( 2Timothy 3:16).
The Law of the Old Testament, “the law of Moses,” was weak and unable to complete the salvation of man from his fallen state and his bending under the temptation of sin. “For on the one hand there is an annulling of the former commandment because of its weakness and unprofitableness, for the law made nothing perfect; on the other hand, there is the bringing in of a better hope, through which we draw near to God…. by so much more Jesus has become a surety of a better covenant” (Hebrews7:18,19,22). That is why God sent His Son to us, to save us and restore the image we were created on His likeness. The role of the law was limited to this; it was put in charge of us until Christ came.“So the law was put in charge of us until Jesus came” (Galatians3:24). So the coming of Jesus is a new covenant for us. God, the lover of humanity, He creates on His image and likeness is revealed, and the hope of salvation is fulfilled.