"...on the first day of the week" (Mark 16:2).
We should think more about Sunday. For starters, we Christians need to remember that Sunday is not part of the weekend. It is rather the first day of the new week.
Then, and this is the most important thing, we need to remember that Sunday is the day our Lord rose from the dead, and that for this reason Sunday became the primary worship day for Christians.
This is quite enough to think about, but there's more.
We may also remember that the first day of creation was a Sunday, on which God said, "Let there be light." And add to this one other thing: the day of Pentecost. It too fell (and falls) on a Sunday.
Now take a step back and see that the Father's first day of creating, the Son's rising as Victor over sin and death, and the Holy Spirit's coming to us with new life all take place on Sunday. Extraordinary! Glorious!! Trinity!!!
Dear Christians, let us do so much more than go to church because we should. Let us go gladly (Ps. 122:1) in the faith of the One who created, redeemed, and makes us holy.
This is the deep meaning of Sunday, and about which we sing in these words:
O day of rest and gladness, O day of joy and light,
O balm of care and sadness, most beautiful, most bright;
This day the high and lowly, through ages joined to bless,
Sing, "Holy, holy, holy," the triune God confess.
This day at earth's creation the light first had its birth;
This day for our salvation Christ rose from depths of earth;
This day our Lord victorious the Spirit sent from heav'n,
And thus this day most glorious a threefold light was giv'n.
(Lutheran Service Book, 906)