Why is the evil still at work? Is God too slow?

We will never go back! God is now dealing with His church worldwide because He is harvesting a Remnant from His Church. The Remnant (truly sold out to Christ) will bring in a great harvest of souls. Then the Rapture, the sudden disappearance of true followers of Christ, triggering the beginning of a 7 year tribulation on earth with God's wrath poured out. See 10 virgins. (1Thes.4:17)