This is part of my liturgy for an Easter celebration of the Lord's Supper. The opening dialogue is from Psalm 118. The first half of the prayer (beginning We thank you, O God, Creator...) is adapted from the German Reformed liturgy, and the second half (beginning We thank you, eternal God, Three-in-One) is from the New Century Hymnal (UCC).
Open now the gates of righteousness,
That we may enter and give thanks to God.
O give thanks to God, for God is good.
God’s steadfast love endures forever.
This is the gate of God.
The righteous shall enter through it.
We thank you, O God, Creator of all that is—sun and moon, stars and galaxies, water and earth, plants and insects,
humans and animals: You are both the Giver and Sustainer of life:
Your Word calls us from darkness into light.