Where is God?

If God exists, why does the world looks so messed up? Why are there injustices and suffering prevailing? If God is reigning but allowing these, is God 'good'? Those are the questions that we might have encountered at least once in our lives. What was your answer to those questions? What would be the bible's answer to those questions? It could be a surprise to someone, but the bible mentions that God has actually left this world. (Gen 6:3) The chairman of Shincheonji Church of Jesus mentions this in his article:
Because of the sin of Adam and the serpent, God left His own creations of heaven and earth. To resolve sin, He gave Moses the law. However, the law did not solve the root cause of sin, therefore the blood of Jesus the righteous one (refer to Heb 10) and the seed of God was required. So Jesus sowed God's seed (Mt 13), and bore the cross to shed his blood. This blood enabled mankind to be freed from sins (Rv 1:5-6) and be reborn of God's seed (1 Pt 1:23). This is recreation.
God gave all creation to Adam, but because Adam has betrayed, sin has entered into the world, and God had to leave the sinful world because He is holy and cannot be with sinful creations. Then who has been governing the world since then? Let's look at Luk 4:5-8.
The devil, leading him up on a high mountain, showed him all the kingdoms of the world in a moment of time. The devil said to him, "I will give you all this authority, and their glory, for it has been delivered to me; and I give it to whomever I want. If you therefore will worship before me, it will all be yours." Jesus answered him, "Get behind me Satan! For it is written, 'You shall worship the Lord your God, and him only shall you serve.'"
This is a scene where the devil is trying to test Jesus. Here, the devil mentions that all the kingdoms of the world have been delivered to him, and Jesus doesn't particularly deny that part. (if that weren't true, it wouldn't have been a test for Jesus in the first place) Okay, so it was the devil who has been governing the world. Would it stay that way forever? No. When the seed Jesus has sown matures, and the era of the Revelation comes, the prophecy of Revelation 21 will be fulfilled, and God will return. When that happens, there would be no more death, mourning, nor any pain.
I heard a loud voice out of heaven saying, "Behold, God's dwelling is with people, and he will dwell with them, and they will be his people, and God himself will be with them as their God. He will wipe away from them every tear from their eyes. Death will be no more; neither will there be mourning, nor crying, nor pain, any more. The first things have passed away.
God has been working thus far to fulfill his promise. True believers should know about this and participate in his work.