I’ve read that at one time, Satan was a beautiful angel in Heaven. But pride was found in him and Satan wanted to elevate himself above God. For this, Satan was cast out of Heaven. This absolutely terrifies me. I do have faith in my Lord and Savior, Jesus Christ. And I also believe that we are saved by grace and that Heaven is perfect. But I am such a wicked, prideful person. What assurance can I have that I would not turn prideful or sinful in Heaven like Satan?
The Lord paid an extreme price for you (1 Peter 1:18-19), and when you gave your life to Him, He accepted responsibility for you and promised never to lose you (2 Cor. 1:21-22, John 6:38-39). At the rapture He will make you as perfect as He is (1 Cor. 15:51-53, 2 Cor. 5:21). He didn’t do any of this for Satan. And He didn’t do it for you just to have you make a mess of things when you get to Heaven. You’re His forever and there’s nothing any one can do to change that (John 10:27-30). And that includes you.