Midrash su Isaia 38:17

R. Jochanan said in the name of R. Jose b. Zimra: "He who depends [for God's help] upon his own merits will [finally] be raised through the merits of others, but he who depends upon others' merits will [finally] be helped because of his own merits. Moses, who depended upon the merits of others, as it is said (Ex. 32, 13.) Remember Abraham, Isaac and Israel, Thy servants, was raised because of his own merits, as it is said (Ps. 106, 23.) He therefore spoke of destroying them, had not Moses, his chosen, stood in the breach before Him. Hezekiah depended upon his own merits, as it is written (Is. 38, 3.) Remember now that I have walked before Thee, but was [finally] raised through the merits of others, as it is said (II Kings 19, 34.) And I will shield the city to save it, for my own sake, and for the sake of David, my servant." And this is [the interpretation] of R. Joshua b. Levi. For R. Joshua b. Levi said: "What is the meaning of the passage (Is. 38, 17.) Behold, for in peace I had great bitterness, i.e., even when the Holy One, praised be He! sent peace unto him, yet he felt bitter [since it was done because of the merits of others] ."