Gentile calendar, The Times of the Gentiles and The Fullness of the Gentiles 526-1 - 2 - 1

"When Darius began his reign in 521 BC Times of the Gentiles (Luke 21:24) had begun; Gentile calendar used.”

“Significant is the fact that a Jewish prophet dated his prophecy according to the reign of a Gentile monarch, rather than by Judean kings in the line of David. This was a vivid reminder to all of Zechariah’s hearers that “the times of the Gentiles” (Cf. Luke 21:24; Dan 2; 7) were in progress and that no descendant of David was sitting on the throne in Jerusalem (cf. Hosea 3:4-5).”

[Chuck Missler, The Prophets of the Post-Exile]

History is often dated relative to world leaders. The last of the kings of Judah had taken into exile, the last king that is until King Jesus returns to earth to reign.

"2. The fullness of the Gentiles (Rom_11:25) is the time of the Rapture, when Christ's Gentile bride will be completed and taken from the earth and when God will resume His dealings with Israel.

3. The times of the Gentiles (Luk_21:24) really began with the Babylonian captivity, 521 b.c., and will extend to the time when Gentile nations will no longer assert control over the city of Jerusalem."

"The fullness of the Gentiles must be distinguished from the times of the Gentiles (Luk_21:24). The fullness of the Gentiles coincides with the Rapture. The phrase “times of the Gentiles” refers to the entire period of Gentile domination over the Jews, beginning with the Babylonian captivity (2Ch_36:1-21) and ending with Christ's return to earth to reign."

[Believer's Bible Commentary]

Romans 11:25, “For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in.”

Although many Gentiles will come to faith during the Tribulation, the Tribulation is primarily devoted to Israel. Israel's blindness pronounced in Luke 13:35, “Behold, your house is left unto you desolate: and verily I say unto you, Ye shall not see me, until the time come when ye shall say, Blessed is he that cometh in the name of the Lord” is removed at the time of the Rapture, nevertheless not all Israel will come to faith in Jesus right away. Conversion will continue throughout the Tribulation with elect remnant will not be become completed Jews until King Jesus returns to earth