Musar к Авот 1:4

The Holy One, Blessed be He, said : "Be jealous for My sake, were it not for envy, the world would not stand. A man would not plant a vineyard, marry a wife or build a house (Shoher Tob 37a). For all of these matters come about because one man envies his companion. If he builds a house, then another person will have it in mind to do likewise, and thus it is concerning a wife. And since the perpetuation of the world depends upon envy, let him dedicate all these envious qualities to God. If he builds a house let him build in it room for the study of Torah, a gathering place for the wise, a place where guests are welcomed, and a place where he does kindness to men. And thus did they say (Shohar Tov ibid). Had not Abraham been jealous he would have not acquired both worlds. And how was he envious? He asked Melchizedek¹See Nedarim 32b, where Melchizedek is identified with Shem, the son of Noah., "How did you emerge from the Ark?" And Melchizedek answered, "Because of the charity that we did there," Abraham said to him, "What kind of charity could you do in the Ark; — were there any poor people there? There was no one there except Noah and his sons, so to whom were you doing charity?" Melchizedek answered him : "With the animals, with the beasts and with the fowl. We did not sleep but were constantly giving food to all these living creatures all night long." At that moment Abraham said, "If these people had not done charity with the animals, beasts and fowl, they would not have emerged from the Ark, but because they did justice with them, they did emerge safely, then I who will do justice with all the children of man who are in the image of the Holy One, Blessed be He, will not this be all the more favorable in God's eyes?" At that moment "And he planted a tamarisk (eshel) in Beersheba" (Gen. 21:33). (The sages take each letter of the Hebrew word Eshel and they say that the word Eshel means a place where strangers can eat, drink and lodge.) In this manner, a man ought to, indeed, increase his zeal.

And thus did our Rabbis interpret the text, "The poor man's wisdom is despised" (Eccl. 9:16). What wisdom of what poor man is despised? It refers to a man who is poor in good deeds; then his wisdom is despised. And if one teaches laws that instruct us to do good and he himself does not do good deeds his words are not accepted, for "not learning but doing is the chief thing" (Aboth 1:17). Wherefore it is necessary tor every man to direct his deeds for the sake of Heaven and see and understand from the example of Elisha, the son of Abuyah : because his father taught him Torah not for its own sake, the son turned to heresy. As it is said in the Jerusalem Talmud (Hagigah 2:1), and in the Midrash (Eccl. Rabbah 7:8, letter 18) : When Elisha, the son of Abuyah was circumcised his father made a feast for the Sages and invited Rabbi Eiezer and Rabbi Joshua and the other Sages, and they sat at the feast and spoke words of the Torah to the extent that a fire came and encircled them. The father of Elisha came and said to them, "My good friends, did you come to burn down the house?" And they said to him, "The fire that you see is only because we are studying the words of the Torah and the Prophets and the Scriptures. And the words of our discussion joyously testify to the truth just as when they were given at Mount Sinai. From Mount Sinai were they given, and from the fire were they given!" The father of Elisha ben Abuyah then said, "Now that I see the power of the Torah, if this my son will live on, I shall give him to the study of Torah." And because the father had it in his mind that he would teach his son Torah not for its own sake but for the power it would give him, his son became a heretic. And even so, a man should study the Torah even if not for its own sake, because from studying it not for its own sake, he will ultimately come to study it for its own sake (Pesahim 50b).