A tranquil heart is life to the body,

But passion is rottenness to the bones

-Proverbs 14:30-

Place me like a seal over your heart, 
like a seal on your arm;
for love is as strong as death, its jealousy unyielding as the grave.
It burns like blazing fire, like a mighty flame.
Waters cannot quench love; rivers cannot sweep it away.
If one were to give all the wealth of one's house for love,
it would be utterly scorned.

-Song of Songs 8:6-7-