Song of Solomon 8:6-7

⁶Set me as a seal upon thy heart, as a seal upon thine arm; for love is strong as death, jealousy is cruel as the grave; the flashes thereof are flashes of fire, a very flame of the LORD.

⁷Many waters cannot quench love, neither can the floods drown it; if a man would give all the substance of his house for love, he would utterly be contemned.