What is the ruling on praying while in doubt about the presence of impurity on one's garment, without the ability to verify it?

If someone doubts the purity of his garment, the Malikis obligate him to sprinkle it with water, whereas the Hanbalis do not consider sprinkling necessary. The Malikis also obligate a person who prayed with it, forgetting its impurity, to repeat the prayer if there is still time, and to repeat it always if he prayed with it intentionally.