Musnad Ahmad Hadith 10247

It is narrated from Abu Huraira (may Allah be pleased with him) that the Holy Prophet (peace and blessings of Allah be upon him) said: A man set out to visit his religious brother who lived in another town. Allah appointed an angel on his way. When he passed by the angel, the angel asked him, "Where are you going?" He replied, "I am going to meet such-and-such a man." The angel asked, "Is there any kinship between you two?" He said, "No." The angel asked, "Is there any favor of his upon you which you are repaying?" He said, "No." The angel asked, "Then why are you going to him?" He said, "I love him for the sake of Allah's pleasure." The angel said, "I have been sent to you by Allah as a messenger to inform you that because of your love for him, Allah loves you."