Three times a year shall all your males appear before the L-rd your G-d

Three times a year shall all your males appear before the L-rd your G-d (Deut. 16:16) In the times of the First and Second Holy Temples, these pilgrimages to Jerusalem were made on the holidays of Passover, Shavuot and Sukkot. However, after Moshiach comes, they will be made every Shabbat and Rosh Chodesh. Furthermore, when Rosh Chodesh falls on Shabbat, two pilgrimages will be made on the same day – one in the morning and one in the afternoon. (Peninei HaGeula)