מוסר אויף ישעיהו 51:16

And the world endures only through Torah, as it is written (Jeremiah 33:25): "If not for My covenant, day and night, the statutes of heaven and earth I would not have ordained." And this is the language of the holy Zohar, Parshath Bereshith 47a: "Everyone who occupies himself with Torah every day will merit having a share in the world to come, and it will be accounted to him as if he had built worlds. For it was through Torah that the world was built and fashioned, as it is written (Mishlei 3:19): 'The L-rd, through wisdom [Torah] founded the earth, etc.' And everyone who occupies himself with it shapes the worlds and sustains them. And come and see: It was with a spirit that the Holy One Blessed be He made the world, and it is with a spirit that it endures, the spirit of those who toil in Torah." And this is the language of Parshath Tzav: " R. Elazar opened and said: (Isaiah 51:16): 'And I have placed My words in your mouth, and with the shadow of My hand have I covered you, etc.' From here we learn that if a man occupies himself with words of Torah and his lips murmur Torah, the Holy One Blessed be He hovers over him and the Shechinah spreads its wings over him. What is more, he causes the world to endure and the Holy One Blessed be He rejoices with him as if the heavens and the earth were planted on that day."

Chazal have said (Sanhedrin 99b): “All who study Torah for its own sake make peace in the celestial and terrestrial retinues, viz. (Isaiah 27:5): ‘Or if he but take hold of My stronghold [Torah], he shall make peace for Me [1]; he shall make peace for Me [2].’ Rav said: ‘It is as if he would build the celestial palace and the terrestrial palace, viz. (Ibid. 51:16): “And I have placed My words in your mouth … to plant the heavens and to lay the foundations of the earth.”’”

(Sanhedrin 99b): “R. Yochanan said: ‘He [one who learns Torah] also secures protection for the entire world, viz. (Isaiah 51:16): “and with the shadow of My hand have I covered you” [and, consequently, the entire world].”’” Levi said: ‘He also brings the redemption nearer, viz. (Ibid.): “and to say to Zion: ‘You are my people.’”’”