כָּל־עֲמַ֥ל הָאָדָ֖ם לְפִ֑יהוּ וְגַם־הַנֶּ֖פֶשׁ לֹ֥א תִמָּלֵֽא׃
Segala jerih payah manusia adalah untuk mulutnya, namun keinginan jiwanya pun tidak pernah terpenuhi.
Akeidat Yitzchak
Research has shown that man's soul grows stronger while feeding on the same foods as the body. The soul eventually assumes an almost independent identity if it remains true to its task. Eventually, it gains the kind of independence from the body which enables it to survive the body as an abstract spiritual entity. We have discussed all this in connection with the verse "He blew into him a spirit of life." In spite of all this, the fact that the soul absorbs the same kind of nourishment as the body has led some people to deny the very possibility of immortality. Since we can observe that the decay of the body is unstoppable, begins in fact almost on the day the baby is born, belief in the independent existence of the soul becomes difficult to accept. The process of gradual death can be understood in this way. If you have a glass of wine that is not quite full, and you add a little water to it in order to fill the glass to the rim, the water added becomes wine. However, in the process, the wine loses a little of its potency. If this process is repeated each time some wine has been sipped from the glass, eventually, the wine will have lost all its potency, and we will wind up with a large quantity of water. Life is a somewhat similar process. The life force gradually spends itself in assimilating the very food that is body building, until finally, having no more reserves, the body dies. Tragically, many have made the error of assuming that the soul dies with the body. If true, this would reduce the stature of man to something inferior to any other creature, since despite man's additional faculties, he alone of all creatures would be the one who labors in vain. Kohelet 6,7, "All man's toil is for the sake of the mouth, yet he cannot satisfy his soul," (appetite) would describe this futility. Based on such misconceptions, man turned to the acquisition of gold etc., objects that are enduring by comparison to himself; he made himself the slave of money, worshipping it as his master. Since we have demonstrated in Chapter twenty-four, that the pursuit of these illusory and transient values is utterly foolish, it follows that the immortality of the thinking part of man is a fact, or man's very creation would not make sense. When Rabbi Yochanan said that Jacob did not die, he merely used Jacob as an example of a maxim that applies to anyone whose immortality has not been forfeited. The reason Jacob served as an example for this lesson, is that he was the third in the line of our ancestors and, as explained in Tanchuma Parshat Mikeytz, "Confidence in one's harvest is not attained when plowing, nor when sowing, but only when the sheaves are ready to be taken into the barn" (Compare also Chapter twenty-five). For this reason, Jeremiah 2,3 describes Israel as G-d’s first "harvest."