When the wicked perish, there is song?

Question:
I am searching for a rabbinic teaching in which God tells the angels not to rejoice over the destruction of the Egyptians at the Reed Sea. Would you help me locate an English translation of this teaching?

Answer:
The teaching can be found in the Babylonian Talmud, Tractate Sanhedrin, folio 39b. Here is a copy of the Soncino translation(with notes)of the relevant passage (from here: http://www.halakhah.com/sanhedrin/sanhedrin_39.html#PARTb):

THEREFORE EVERY SINGLE PERSON etc. And there went out the song5 throughout the host:6 R. Aha b. Hanina said: [It is the song referred to in the verse.] When the wicked perish, there is song;7 [thus] when Ahab b. Omri perished there was 'song'. But does the Holy One, blessed be He, rejoice over the downfall of the wicked? Is it not written, [That they should praise] as they went out before the army, and say, Give thanks unto the Lord for His mercy endureth for ever;8 concerning which R. Jonathan asked: Why are the words, He is good9 omitted from this expression of thanks? Because the Holy One, blessed be He, does not rejoice in the downfall of the wicked.10 For R. Samuel b. Nahman said in R. Jonathan's name: What is meant by, And one approached not the other all night?11 In that hour the ministering angels wished to utter the song [of praise]12 before the Holy One, blessed be He, but He rebuked them, saying: My handiwork [the Egyptians] is drowning in the sea; would ye utter song before me!13 — Said R. Jose b. Hanina: He Himself does not rejoice, yet He causes others to rejoice. Scripture supports this too, for it is written, [And it shall come to pass, that as the Lord rejoiced over you to do good … so yasis will the Lord] cause rejoicing [over you by destroying you],14 and not yasus [so will the Lord rejoice etc.]15 This prove it.

1. [H], E.V. 'cry'.
2. I Kings XXII, 36, with reference to Ahab's death at Ramoth in Gilead.
3. [H] Prov. XI, 10.
4. II. Chron. XX, 21, with reference to Jehoshaphat king of Judah, when he went to engage in war with the Ammonites and Moabites.
5. [H], as in Ps. CVII, 1.
6. [H], can also be rendered 'it is good'.
7. Ex. XIV, 20.
8. Cf. Isa. VI, 3. And one (angel) called unto another, and said, Holy, holy, holy, etc.
9. The verse is thus taken to mean that one (angel) did not approach the other, calling upon him to join in the Song (Maharsha).
10. Deut. XXVIII, 63. [H], in the Hiphil (causative).
11. [H], in the Kal.