Where the word Tribulation comes from!

tribulum - (Latin) wooden sled pulled over wheat to separate the chaff.

The first group to be raptured is the barley passover (Rev. 12.5, 14.1-5) first rapture, a soft firstfruits according to readiness (Rev. 3.10, Luke 21.36, Matt. 24.42). The Pentecost pertains to the wheat in the tribulum, signifying further raptures during the Tribulation where martyrs are raptured individually 3.5 days after they go to rest like the Two Witnesses. The 7 types of fruits (Deut. 8.8) are the final harvest (Rev. 14.14-16) at the last trumpet of the Tribulation. The final harvest is not the millennial kingdom. The feast of tabernacles is the millennial kingdom.