Pope Pius IX declared by reciting the following prayer five times on a Friday, we free five souls from purgatory and thirty-three souls on Good Friday.

The prayer should be recited before a crucifix with contrite heart; praying a few moments for the the poor souls of purgatory:

I adore you, oh glorious cross, which was adorned with the heart and the body of my Savior, Jesus Christ, stained and covered with blood.  I adore you, oh holy cross out of love for Him, Who is my savior and my God.