Zirr bin Hubaysh (may Allah have mercy on him) says: I came to Sayyiduna Safwan bin Assal (may Allah be pleased with him), and he asked: "What has brought you?" I said: "The search for knowledge." He said: "The angels spread their wings for the seeker of knowledge out of pleasure with what he seeks." I said: "I felt a doubt in my heart about wiping over the leather socks after defecation and urination, and I was one of the Companions of the Messenger of Allah (peace and blessings be upon him), so I have come to you to ask about that. Did you hear anything from him (peace and blessings be upon him) about it?" He said: "Yes, he (peace and blessings be upon him) used to order us, when we were on a journey, not to take off our leather socks for three days and nights except for major ritual impurity (janabah); but for defecation, urination and sleep (we should not take them off)." I asked: "Did you hear him say anything about love?" He said: "Yes, we were with him (peace and blessings be upon him) on a journey when a Bedouin called out to him (peace and blessings be upon him) in a loud voice (the narrator Ibn Uyaynah was uncertain about the word here): 'O Muhammad!' He (peace and blessings be upon him) answered him in the same manner and said: 'Wait.' He asked: 'What do you say about a man who loves a people but has not joined them?' He (peace and blessings be upon him) said: 'He will be on the Day of Resurrection with the one he loves.'" He said: "Then he (peace and blessings be upon him) kept on talking to us until he said: 'Towards the west there is a door whose width is the distance of a journey of seventy years. Allah opened it for repentance on the day He created the heavens and the earth, and He will not close it until the sun rises from its direction.'"
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7322