The Church of God believes in Christ Ahnsahnghong as God because He fulfilled all the prophecies of the Bible about Second Coming Christ.
Jesus Fulfilled the Prophecies of the Bible
The Bible proves that Jesus is the Christ and God (Jn 5:39). The Bible already prophesied where Christ would be born, how He would appear, and what He would do, even before Jesus came. This is why Jesus testified about Himself through the Bible, and His disciples too testified that Jesus is the Christ through the prophecies of the Bible (Lk 24:27; Ac 17:2–3; 8:30–35).
Christ Ahnsahnghong Fulfilled the Prophecies of the Bible
The Bible also testifies that Ahnsahnghong is God and the Christ who came a second time. The Bible prophesied where and how Christ would appear a second time and what He would do, just as it did about His first coming. Christ Ahnsahnghong fulfilled all those prophecies.
The Bible testifies that the One who saves all humanity by restoring the lost truth of the New Covenant is Second Coming Christ. No one was able to restore the truth of the New Covenant for a long time, but Christ Ahnsahnghong fully restored it in this age. This is why the Church of God believes that Ahnsahnghong is God and the Christ who came a second time according to the prophecy of the Bible.