Oh, there is indeed a "rapture." This will take place in the next resurrection. Believers will be changed in a twinkling of an eye. Whether it come by the mouth of his prophets or Christ Himself, it is the same.
And we are saved by and because of His grace. Nothing we can do outside of sincere repentance will save us. His grace is what reaches in and saves us from the penalty of the law. But once saved, we are called to keep his commandments and to do His work, and we are judged according to our efforts, so I agree here.
Matthew 7:21
21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
The parable of the sower alludes to this principle. According to His own words those who follow Him, and give up homes, etc in order to do so, shall receive an hundredfold. Some shall receive a kingdom, even as His Father has given Him.
Luke 22:29
29 And I appoint unto you a kingdom, as my Father hath appointed unto me;