On Going to Confession Before Mercy Sunday
Jesus said to St. Faustina about Divine Mercy Sunday "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 graces flow are opened."
It is impossible for everyone to go to confession on Divine Mercy Sunday. We encourage everyone to go beforehand. This great article by Dr. Robert Stackpole (Director of the JP2 institute for Divine Mercy) explains that going to confession during Lent and remaining in a state of grace is sufficient to recieve the graces of our Lord's promise of Divine Mercy Sunday.
"Some people seem to believe that you have to go to Confession on the very feast day itself! But nowhere in St. Faustina's Diary does it stipulate this. In fact, we know from Diary entry 1072 that St. Faustina made her confession in preparation for Divine Mercy Sunday on the day before the feast, on a Saturday."