Zirr bin Hubaish (may Allah have mercy on him) says that one day I went to Hazrat Safwan bin Assal (may Allah be pleased with him) to ask about the ruling of wiping over leather socks. He asked, "What brings you here?" I said, "I have come in pursuit of knowledge." He said, "Shall I not give you glad tidings? The Messenger of Allah (peace and blessings be upon him) said: 'Allah's angels spread their wings for the seeker of knowledge, expressing happiness for what he seeks.'" Then he mentioned the entire hadith.