371. IX. THAT WITH MARRIED PARTNERS WHO TENDERLY LOVE EACH OTHER, JEALOUSY IS A JUST GRIEF FROM SOUND REASON, LEST THEIR CONJUGIAL LOVE BE DIVIDED AND THUS PERISH. Within all love is fear and grief, fear lest it perish, and grief if it does perish. There is the like fear and grief in conjugial love, but the fear and grief of this love is called zeal or jealousy. That with partners who tenderly love each other this zeal is just and from sound reason, is because it is at the same time fear for the loss of eternal felicity, not only his own but also his partner's; and because it is also a protection against adultery. As regards the first point--that it is a just fear for the loss of his own and his partner's eternal felicity--this follows from all that has hitherto been advanced respecting love truly conjugial, and also from the fact that from that love comes the blessedness of their souls, the happiness of their minds, the delight of their bosoms, and the pleasure of their bodies; and because these remain with them to eternity, there is fear for each other's eternal happiness. [As regards the second point]--that the zeal is a just protection against adulteries--this is evident; therefore it is as a fire blazing out against violation and defending itself against it. From this it is evident that one who tenderly loves his partner is also jealous; but the jealousy is just and sane according to the wisdom of the man.