Musar for Deuteronomy 7:11

Yes, my brother, is this world not "market day," when one must buy the wares to feed his soul all the days of his long life in the world that is entirely long? And if now, on "market day," he luxuriates in laziness and shirks his labor, will his soul not starve in the world of eternal life? This is the intent of "If not now, when?" And thus, in Koheleth (9:10): "And all that your hand finds to do, do with your power." That is, do not work lazily, but to the limits of your power. For only now is the time of doing, for (Ibid.): "there is no doing or reckoning or knowledge or wisdom in Sheol, whither you are going." For the days of labor will already have ended, and only from what is prepared for him by his toils in the days of his life in this world will his soul live there. As written in the Torah (Devarim 7:11): "…today to do them [the mitzvoth]," and not tomorrow to do them, but only to receive their reward. (Eruvin 22a)

[In sum, one must know that he has come to this world only for a specified time, for Torah and mitzvoth, and that he is destined to return to the higher world to receive his reward. As it is written (Devarim 7:11): "which I command you today to do them," concerning which our sages of blessed memory have said: "Today to do them, and tomorrow to receive their reward." But, the yetzer hara entices a man in his youth, that he yet has many years to live, and, in truth, this is an error, as we have written above. For each day is given him by the Blessed Creator with exact accounting, as it is written (Job 7:1): "Does a man not have an allotted time upon the earth?" And he cannot exempt himself from this day in anticipation of the next day. A man in this world is like one who has come to sojourn in a distant land for a specific time, as it is written (Psalms 119:19): "I am a sojourner in the land; do not hide Your mitzvoth from me." He must pity each day, that it not go to waste.

We find that a desirable death for man is the exact opposite of what is deemed a desirable death for the animal. Whereas man prefers death at the hands of G–d, i.e. not through murder at the hands of human beings, the animal achieves its state of "holiness" only when executed by man, not when it dies from natural causes. The reason is that man's body is the sheath for his soul. Through partnership of body and soul man observes the laws of Torah and Avodah in the sense of היום לעשותה ולמחר לקבל שכרם, to perform the commandments "today" while alive on earth, and to receive the reward for such performance "tomorrow," i.e. after death of the body, in the Hereafter. This is why the day of death is described by Solomon as superior to the day a person is born, since it is the day the spirit returns to G–d and the body finds rest in the grave (Kohelet 7,6). If body and soul are separated prematurely (through murder or other violence leading to death), whoever is responsible has separated Torah and Avodah from the direction and the time frame intended by G–d for that person.