The phrase "great tribulation" refers to a period of severe hardship, suffering, or distress. It describes a time when people may face significant challenges or difficulties. Full definition
Already in the Book of Revelation, the martyrs are lauded as white - robed saints in heaven who have «come through great tribulation» (Rev. 7:14). (firstthings.com)
Jesus Christ's wife are those who endure great tribulation until the end (telos) as the seventh trumpet begins to sound, they will refuse to fall away (2Thess.2: 1 - 4), they will refuse the mark of the beast and will prefure death for their testamony of Jesus Christ fulfilling the prophecy of the fifth seal (Rev. 6:9 - 11). (religion.blogs.cnn.com)
When everything is tabulated carefully, the end of the 3rd Great Tribulation falls on May 21 this year. (religion.blogs.cnn.com)