Sayyiduna Qays bin Asim (may Allah be pleased with him) came to the Prophet (peace and blessings be upon him), met him in private and accepted Islam. The Prophet (peace and blessings be upon him) ordered him to take a ritual bath with water and lote-tree leaves, and he bathed. Then the prayer was called, and he entered between Abu Bakr and Umar (may Allah be pleased with them both) and stood between them. When the prayer was finished, the Prophet (peace and blessings be upon him) said: "Qays bin Asim has asked me about three things which no one but Abu Bakr has asked me about."
Hadith Referenceالمعجم الكبير للطبراني / باب القاف / 15958