Purity of the heart is a condition for conversing with the truth or witnessing it, a condition of obligation and a condition of validity together. The reason for this is that we are in the place of obligation, and faith is required of us in God and in what has come from Him and in the Messenger and the Messengers. This is an indication that the matter is not limited except that it is high, highest, and above all who have knowledge. All-Knowing, Exalted in ranks, He raises the ranks of whom He wills.