The Prophet (peace and blessings of Allah be upon him) said:
“O people, listen and understand. Allah has slaves who are neither prophets nor martyrs, but both the prophets and martyrs envy them for their closeness to Allah.” A bedouin stepped forward, pointed to the Messenger of Allah and said, “O Messenger of Allah, tell us about these people.” The Prophet was pleased with the bedouin’s request and said, “They are from various peoples and tribes who have no ties of relationship between them. They love each other purely for the sake of Allah. On the Day of Resurrection, Allah will present them pulpits of light for them to sit on. Their faces will be light and their clothes will be light. The people will be scared on the Day of Resurrection, but they will not be scared. They are the friends of Allah who will not have any fear upon them nor will they grieve.
[Ahmad and Abu Ya’la with a hassan chain)
“A man set out to visit a brother (in Faith) in another town and Allah sent an angel on his way. When the man met the angel, the latter asked him, “Where do you intend to go?” He said, “I intend to visit my brother in this town”. The angel said, “Have you done any favour to him?” He said, “No, I have no desire except to visit him because I love him for the sake of Allah, the Exalted, and Glorious.” Thereupon the angel said, “I am a messenger to you from Allah (to inform you) that Allah loves you as you love him (for His sake)”. [Muslim]