Seriously, what does this mean?

I bought two glasses at Home Plus tonight. Along with leaf, there is an inscription on both glasses that reads:

"Without love and laugher there is no joy.
Love abounds in honey and poison
Where there is no jealousy there is no love."

What!? Love abounds in honey and poison? I'm sure that there's a deep thought here, I just think that the author of this inscription was insane--insane enough to kill the person he loved?