Because Satan HATES the doctrine of the Resurrection/Rapture.
That God in His grace, mercy, and lovingkindness not only saves vile sinners from the degradation of sin and evil, but He actually transforms them supernaturally, so that they are fully perfected -- body, soul, and spirit (physically, morally, and spiritually), and resemble Christ for eternity. If the New Birth is a miracle, this is a stupendous miracle.
The saints will literally radiate light (as do God and Christ) and that is the meaning of "glorification". That is also why they are called "children of light". The light of the glory of God is in the face of Jesus Christ, therefore all the saints will resemble him for eternity. This will enable perfect union and communion with God and Christ.
Furthermore, the saints will have "physical-spiritual" bodies (similar to the angels) which means they will no longer be subject to the limitations of humanity on earth. They will be able to travel from the New Jerusalem to the New Earth within nanoseconds, take care of business, and return at the end of the day!
All of this is there in the Bible for those who are prepared to diligently study the word. But of course, as Peter has already warned us,, there will be scoffers in the last days saying "Where is the promise of His coming"?