Midrash sa Exodo 17:5: Mekhilta DeRabbi Yishmael, Ein Yaakov (Glick Edition), Midrash Tanchuma & Shemot Rabbah

(Exodus 17:5) "And the L–rd said to Moses: Pass over, etc.": Pass over (i.e., overlook) their words. R. Yehudah says: Pass by them, for you will find water for them. R. Nechemiah says: Forgive their sin. Variantly: "Pass before the people" and whoever is bothered, let him speak!

Reuben went in the days of harvest, etc. Raba b. Isaac said in the name of Rab: "Infer from this that the righteous do not stretch their hands out to robbery." What were the dudaim which Reuben found? Rab said: "They were mandrakes," and Samuel said: "Violet flowers." R. Alexandri said: "Those who occupy themselves with the Torah for its own sake [for no selfish ends] cause peace to reign in the heavenly household and in the household here below," as it is said (Is. 27, 15) "If he would but take hold of my strength, make peace with me, make peace with me." And Rab said: "He is considered as if he had built both palaces of heaven and earth," as it is said: (Ib. 51, 16) "And I have placed My words in thy mouth, and with the shadow of My hand have I covered thee: To plant the heavens and lay the foundations of the earth." R. Jochanan said: "He also protects the world, as it is said (Ib.) "With the shadow of My hand have I covered thee." And Levi said: "He brings nearer the redemption, as it is said (Ib.) To say to Zion, Thou art My people." Resh Lakish said: "He who teaches the Torah to his neigbor's son, is considered by Scripture as if he had created him," as it is said: (Gen. 12, 5) "And the persons they had obtained Charan." R. Elazar said: "He is considered as the creator of the law, as it is said: (Deut. 29, 8) Keep ye, therefore, the words of the covenant, and do them." And Raba said: "He is considered as the creator of himself," as it is said, "And do them; do not read otham (them), but atem, (ye yourselves)." R. Abahu said: "He who causes his neighbor to do a meritorious act, is considered by Scripture as if he himself has done it, for it is said: (Ex. 17, 5) "And take in thy hand thy staff wherewith thou smotest the river, and go." Did he, then, smite the river? Did not Aaron do this? But this is to teach thee that whoever causes his neighbor to do a meritorious act is considered by Scripture as if he himself had done it."

And we are hereby apprised that the captives rejoiced in all the decrees inflicted by Pharaoh upon Israel, (for which they were punished) in keeping with (Mishlei 17:5) "He who rejoices in (another's) misfortune will not be absolved," and (Psalms 24:17) "Do not rejoice in the downfall of your foe," and (Ezekiel 26:2-3) "Son of man, because Tyre said about (the besieged Jerusalem) 'Heach!' (an expression of joy) — thus said the L–rd G–d: 'Behold, Tyre, I am (coming) against you, and I will raise up many nations against you, as the sea raises its waves!'" And not only captives alone (were thus smitten), but even men-servants and maid-servants, viz. (Exodus 17:5) "… until the first-born of the maid-servant."