In the West at least it is the case that most if not all of us are able to spend a considerable amount of time doing things we enjoy. That is of course a good thing and is, in large part, the result of our being blessed by God.
Its also true that there is a sort of drag that can become part of the day to day (going to work, school etc.) Yet, I imagine we are mostly pretty comfortable with our weekly patterns. Five days or so of work and plenty of time for visiting and or recreation on Saturday. The days run on but even in our very secular society one day is different. Sunday. Sundays are different for even today most folks go to church on Sunday.
That is of course a big question but I can say a few smallish things about it. To start its important to remember that it was on a Sunday that Jesus friends first met Him as He is now and ever shall be: Risen in Victory over Death. That is something that still happens by the way. It is on Sunday that we meet Jesus in a way that is really unavailable to us during the rest of the week. It is the day on which we meet and renew and grow our relationship with Him, as a people. Its on Sunday that we gather together with God The Father, Son and Holy Ghost and the whole Church living and dead to celebrate what truly is and see the world as it is becoming . Sunday then is (among other things) a picture of the New Heavens and Earth. Its an acquired taste for sure, but its on we can learn to savor and enjoy.