Narrated Ibn Mas’ood (may Allah be pleased with him), the Prophet (peace and blessings of Allah be upon him) said: “Our Lord admires two men: a man who leaves his mattress and cover, and slips away from his wife and lover, to go and pray. Allah says, ‘O My angels, look at My servant. He has left his mattress and cover and slipped away from his wife and lover, out of hope for what is with Me and out of fear of what is with Me.” Al-Mu'jam al-Kabeer by al-Tabarani (10/179)
When Allah says to His Angels "look at My servant", He boasts about His servant. "look…" means to consider with mercy, which entails asking for forgiveness and intercession. Allah says "My" to honor this servant because he abandoned the comfortable surroundings to stand before the Lord and pray. "Out of hope"… without any hypocrisy or boasting, rather hoping for "what is with Me" which means Paradise and reward from Allah, and the contentment of the Lord and meeting Him on the Day of Judgment. "Out of fear"… means fearing and avoiding "what is with Me," which indicates the Hellfire and all kinds of punishment.
Mura'at al-Mafateeh Sharh Mishkat al-Masabeeh (4/252)
In Saheeh ut-Targheeb, with a reliable source: "Indeed Allah laughs at two men: A man who stands during the cold night, away from his bed, his bedsheet and his blanket. He performs ablution then stands for prayer. So Almighty Allah says to His angels: “What has this servant of Mine carried along with this action of his?” The angels say: “Our Lord, hope for what is with You and fear for what is with You.” Then Allah says: “I have given him what he hoped for and I have secured him from what he fears...”
Saheeh ut-Targheeb (1/402)