The request for Divine Mercy Sunday did not come from Blessed John Paul II, but from Jesus Christ himself:
On one occasion, I heard these words: My daughter, tell the whole world about My Inconceivable mercy. I desire that the Feast of Mercy be a refuge and shelter for all souls, and especially for poor sinners. On that day the very depths of My tender mercy are open. I pour out a whole ocean of graces upon those souls who approach the fount of My mercy. The soul that will go to Confession and receive Holy Communion shall obtain complete forgiveness of sins and punishment. On that day all the divine floodgates through which grace flow are opened. Let no soul fear to draw near to Me, even though its sins be as scarlet. My mercy is so great that no mind, be it of man or of angel, will be able to fathom it throughout all eternity. Everything that exists has come forth from the very depths of My most tender mercy. Every soul in its relation to Me will I contemplate My love and mercy throughout eternity. The Feast of Mercy emerged from My very depths of tenderness. **It is My desire that it be solemnly celebrated on the first Sunday after Easter. Mankind will not have peace until it turns to the Fount of My Mercy. **(Diary 699)
Now, as has been stated here, this is private revelation and no Catholic is under obligation to accept this under pain of sin. Personally, I don’t know why anyone would reject it, but I know that some do. But just because some do reject it, we have no right to judge them.
I don’t completely understand the purpose of this thread. Okay, so some guy on some blog says he doesn’t like Divine Mercy Sunday. He attacks the Pope, but if he read St. Faustina’s diary, he would realize that this did not come from JPII but from Christ himself. The writer from the blog represents himself, not all “traditionalists” or any other group of people. Why are “traditionalists” being singled out?
I think we need to be really be careful about quoting from blogs and then applying them to whole groups of people.