3,577. When Vidui Maaser is Recited

Hilchos Maaser Sheini and Neta Revai 11:2

The tithe confession is only made after the year in which the tithe for the needy is taken. This is derived from Deuteronomy 26:12-13: “When you finish taking tithes, you shall declare before Hashem your God (saying), 'I have removed all the sacred things from the house.…'"

Hilchos Maaser Sheini and Neta Revai 11:3

The tithe confession is made on the afternoon of the last day of Pesach in the fourth and seventh years of the shemittah (sabbatical) cycle, as the aforementioned verse says: "When you finish taking tithes...," meaning the holiday when all the tithes are finished. Pesach in the fourth year doesn’t arrive before all of the various types of produce - both those of the ground and those of the trees - have been tithed.