Charles Ellicott Commentary Zechariah 8:18-23

"And the word of Jehovah of hosts came unto me, saying, Thus saith Jehovah of hosts: The fast of the fourth [month], and the fast of the fifth, and the fast of the seventh, and the fast of the tenth, shall be to the house of Judah joy and gladness, and cheerful feasts; therefore love truth and peace. Thus saith Jehovah of hosts: [It shall] yet [come to pass], that there shall come peoples, and the inhabitants of many cities; and the inhabitants of one [city] shall go to another, saying, Let us go speedily to entreat the favor of Jehovah, and to seek Jehovah of hosts: I will go also. Yea, many peoples and strong nations shall come to seek Jehovah of hosts in Jerusalem, and to entreat the favor of Jehovah. Thus saith Jehovah of hosts: In those days [it shall come to pass], that ten men shall take hold, out of all the languages of the nations, they shall take hold of the skirt of him that is a Jew, saying, We will go with you, for we have heard that God is with you." — Zechariah 8:18-23 (ASV)

This fourth section gives at last all that the prophet sees fit to answer concerning the fast of the fifth month (Zechariah 7:3), and also concerning the other fasts. On the 9th or 17th of “the fourth” month (Tammuz) Jerusalem was taken by Nebuchadnezzar, in the eleventh year of Zedekiah (Jeremiah 39:2; Jeremiah 52:6–7). On the tenth of “the tenth” month (Tebeth) siege was laid to Jerusalem by Nebuchadnezzar, in the ninth year of Zedekiah (2 Kings 25:1; Jeremiah 52:4). As, on account of their sins, their feasts had been changed into fasts, and their days of rejoicing into mourning (Amos 8:10), so now the prophet promises that provided they keep the required conditions their fasts would be transformed into feasts.

No express command is given regarding the abolition of the fasts; but according to Jewish tradition (T.B. Rosh Hashshanah, 18 b), when the nation was in peace and prosperity the fasts were suspended; when it was in trouble again the fasts were resumed. Since the destruction of the Temple by Titus, the Jews have kept the following fasts: the seventeenth of Tammuz, the ninth of Ab, the third of Tishri, and the tenth of Tebeth, on account of various calamities which took place on those days.