John 16:21

A woman in labor is in pain because her time has come; but no sooner is the child born, than she forgets her trouble in her joy that a man has been born into the world.

Revelation 7:14-17

'My Lord,' I answered, 'it is you who know.' 'These,' he said, 'are they who come through the Great Persecution; they washed their robes white in the blood of the Lamb.

Treasury of Scripture Knowledge

Summary

Because thou shalt forget thy misery, and remember it as waters that pass away:

Bible References

Because

John 16:21
A woman in labor is in pain because her time has come; but no sooner is the child born, than she forgets her trouble in her joy that a man has been born into the world.
Revelation 7:14
'My Lord,' I answered, 'it is you who know.' 'These,' he said, 'are they who come through the Great Persecution; they washed their robes white in the blood of the Lamb.