15 Celebrate the Feast to God, your God, for seven days at the place God designates. God, your God, has been blessing you in your harvest and in all your work, so make a day of it - really celebrate! 16 All your men must appear before God, your God, three times each year at the place he designates: at the Feast-of-Unraised-Bread (Passover), at the Feast-of-Weeks, and at the Feast-of-Booths. No one is to show up in the Presence of God empty-handed; 17 each man must bring as much as he can manage, giving generously in response to the blessings of God, your God.
Matthew Henry's Commentary on Deuteronomy 16:15-17
Commentary on Deuteronomy 16:1-17
(Read Deuteronomy 16:1-17)
The laws for the three yearly feasts are here repeated; that of the Passover, that of the Pentecost, that of Tabernacles; and the general law concerning the people's attendance. Never should a believer forget his low estate of guilt and misery, his deliverance, and the price it cost the Redeemer; that gratitude and joy in the Lord may be mingled with sorrow for sin, and patience under the tribulations in his way to the kingdom of heaven. They must rejoice in their receivings from God, and in their returns of service and sacrifice to him; our duty must be our delight, as well as our enjoyment. If those who were under the law must rejoice before God, much more we that are under the grace of the gospel; which makes it our duty to rejoice evermore, to rejoice in the Lord always. When we rejoice in God ourselves, we should do what we can to assist others also to rejoice in him, by comforting the mourners, and supplying those who are in want. All who make God their joy, may rejoice in hope, for He is faithful that has promised.