Michael LeFebvre (The Liturgy of Creation) looks at the rhythm of the ancient Israelite calendar as recorded in the Pentateuch to provide insight into the creation narrative in Genesis 1. The festivals of Israel are outlined in detail, and provide a window on these rhythms.
Israel's festival calendar was not a liturgy for worship divorced from daily life but a rhythm for worship that helped regulate both risk spreading and labor optimization for national fruitfulness. (p. 39)
The festivals (especially through the lens of the exodus narrative mapped over them ...) taught the people to view themselves as stewards of a land that God had given them. They were being taught to maximize the fruitfulness of the land with gratefulness and with God's love for the poor on their hearts. (p. 45)
The festivals in the spring coincided with the barley harvest and the wheat harvest. In both cases the firstfruits are presented to God. It is not clear how LeFebvre views the timing and authorship of the books of the Pentateuch, particularly Deuteronomy. He argues from a reference frame where the festivals outlined in Deuteronomy 16 require pilgrimage to Jerusalem and presentation of offerings at the temple. As temple worship centered in Jerusalem dates far later than the exodus setting assumed in Deuteronomy, this would suggest a relatively late date for the text. We read in the New Testament of pilgrimages to Jerusalem - but it is not clear how early these regular pilgrimages started. It would be interesting to hear from someone with the necessary expertise on this point.
Independent of this issue, it is clear that the rhythm of festival worship is tied to a communal life together and to the agricultural cycles of the year in ancient Israel. LeFebvre suggests that the festivals provided a means to work together in the harvest and to provide for those who lacked sufficient food and resources. Certainly the need for such generosity is made clear in the outline of festivals in Leviticus 23.
“‘When you reap the harvest of your land, do not reap to the very edges of your field or gather the gleanings of your harvest. Leave them for the poor and for the foreigner residing among you. I am the Lord your God.’” Lev. 23:22
The festivals have practical and theological significance.
The Fall festivals came after the summer season when summer fruits, grapes, dates, figs, olives, and pomegranates had been harvested and the firstfruits of these crops would be offered. Again, these (except for the Day of Atonement) were communal feasts.
Israel's national harvest calendar brought the community together at key points around harvests and established a diversified economy as the ideal. More importantly, the festivals were knit together by the exodus narrative. The story of Israel's exodus from Egypt (Passover), their constitution as a nation at Sinai (Weeks), and their journey to the Promised Land (Booths) provided an overarching religious vision for the people's yearly privilege and duty as heirs of the land. The festivals provided a blend of practical, agricultural structure as well as theological inspiration to govern their stewardship of the land before God. The theological aspect of these festivals helped people to pursue household prosperity with a right heart before God and love for the needy around them. God gave them the land, and it was his blessing alone that would keep them in it. (p. 53)
The calendar sets a rhythm for life and worship that keeps the people focused on God.
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