Divine Mercy Sunday is observed on the octave of Easter; the feast will be celebrated on April 16th this year.
The devotion originated with St. Maria Faustina Kowalska, a Polish nun who kept a diary in the 1930s of Christ's private revelations, teller her of His message of mercy. She wrote that she first saw a vision of Jesus on Feb. 22, 1931. He had rays of mercy streaming from His heart.
By reciting the novena (a novena is prayed for nine days), we can receive a plenary indulgence. This is a special type of indulgence that, if all the requirements are met, removes all temporal punishment due to one's sin or for someone else.
Booklets are located on the tables in the back of the churches.