1 Samuel 6:3
And they said, If ye send away the ark of the God of Israel, send it not empty; but in any wise return him a trespass offering: then ye shall be healed, and it shall be known to you why his hand is not removed from you.
A Random Prayer...
Prayers and Passages of St. Alphonsus De Liguori
He who prays is certain to be saved; while he who prays not is certain to be damned. All the saints were saved, and came to be saints by praying; all the accursed souls in hell were lost through neglect of prayer; if they had prayed, it is certain that they would not have been lost. And this will be one of the greatest occasions of their anguish in hell, the thought that they might have saved themselves so easily; that they had only to beg God to help them, but that now the time is past when this could avail them (from The Necessity of Prayer).
more prayers...