Look, I go to church every Sunday. Every "other" Sunday.

After the 6th day of creation, God rested on the 7th day to marvel at the goodness of His creation (Gen 1:31; 2:1-3). He would later explicitly command His people to rest from their labor on the 7th day, that they might likewise marvel at the fruit of His labor.

"The heavens declare the glory of God, and the sky above proclaims his handiwork."
~Psalm 19:1

After Christ's work on the cross, His people would gather on the 1st day to reflect on Christ's work of redemption in making atonement for His people. Jesus appeased the wrath of God for His people who are new creations in Christ (2 Cor 5:17) and we marvel at what Christ's has done on the cross and what the Spirit is doing in those new creatures. (cf. Phil 2:13; Gal 5:22-23)

"We gather together on the first rather than the seventh day of the week because redemption is even a greater work than creation and more worthy of commemoration and because the rest which followed creation is far outdone by the rest which ensues upon the completion of redemption. Like the Apostles, we meet on the first day of the week and hope that Jesus may stand in our midst and say, 'Peace be unto you.' Our Lord has lifted the Sabbath from the old and rusty hinges where on the law had placed it long before and set it on the new golden hinges which His love has fashioned. He has placed our rest day not at the end of a week of toil but at the beginning of the rest which remains for the people of God. Every first day of the week we should meditate on the rising of our Lord and seek to enter into the fellowship with Him in His risen life."
~Charles Spurgeon