The Feast of Pentecost: All Males to Attend
Source: TTT
Exodus 23:16, 17
You are also to keep the Feast of Harvest with the firstfruits of the produce from what you sow in the field. And keep the Feast of Ingathering at the end of the year, when you gather your produce from the field. / Three times a year all your males are to appear before the Lord GOD.
Deuteronomy 16:16
Three times a year all your men are to appear before the LORD your God in the place He will choose: at the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Tabernacles. No one should appear before the LORD empty-handed.