This feast is memorial of the blowing of trumpets. Trumpets were blown primarily to gather people for a journey, judgment, or battle. When we think about the fall feast pertaining the second advent the way the spring feast pertain to the first advent, then we can surmise that the tribulation could very possibly begin one year on the very day that celebrates the Feast of Trumpets - the 1st day of Tishrie (on the Jewish calendar).