John 16:21

A woman, when she is in travail, has sorrow, because her hour came; but, when she bears the child, she no longer remembers the anguish, because of the joy that a man was born into the world.

Revelation 7:14-17

And I have said to him, "My lord, you know." And he said to me, "These are those who come out of the great tribulation; and they washed their robes, and made them 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, when she is in travail, has sorrow, because her hour came; but, when she bears the child, she no longer remembers the anguish, because of the joy that a man was born into the world.
Revelation 7:14
And I have said to him, "My lord, you know." And he said to me, "These are those who come out of the great tribulation; and they washed their robes, and made them white in the blood of the Lamb.