Whom having not seen, ye love; in whom, though now ye see him not, yet believing, ye rejoice with joy unspeakable and full of glory:

You love someone you haven't seen; and even though you can't see them now, you still believe in them, which makes you extremely happy with a joy that words can't describe and is filled with glory.

King James Version

Simple English

* Work in progress - there may be occasional inaccuracies