My friend says although in the temptation of Jesus in the wilderness it was legitimate when Satan offered the kingdoms of the world to Jesus, everything changed after the cross and because of Matthew 28:18 all the world, authority, and power was once again in Jesus ownership. I tried to explain that although this is true, the consummation of both our salvation, as well as His kingdom will occur in a future time – our bodies at our glorification and His kingdom at His second coming. Are there scriptures I can use to help him understand that Satan is still the god of this world and in control, as God allows him to be?
It is true that in Matt. 28:18 Jesus said He had been given all authority in Heaven and on Earth. He said this in 32 AD after His resurrection, because His Father had promised Him the nations as His inheritance (Psalm 2:8-9). But He didn’t take control of Earth at the time. We know this because about 20 years later Paul said the creation was still waiting to be liberated from its bondage to decay (Romans 8:20-22), and a few years later he referred to Satan as the god of this age (2 Cor. 4:3-4). 30 years after that, John wrote that the whole world is still under the control of the evil one (1 John 5:19).
Finally, in Rev. 11:15, at the time when the 7th trumpet will sound, Jesus will take charge of the kingdom of the world, and 3 1/2 years later, after He has vanquished His enemies, He will return to Earth to begin His reign as King of the whole Earth (Zechariah 14:9) This will happen at the time of the 2nd Coming. Until then, 1 John 5:19 still applies; the whole world is under the control of the evil one.