Abdullah bin Utbah (may Allah have mercy on him) says: Once Sayyiduna Ibn Mas'ud (may Allah be pleased with him) was making a supplication in the mosque when the Prophet (peace and blessings be upon him) and Sayyiduna Abu Bakr (may Allah be pleased with him) passed by him. When the Messenger of Allah (peace and blessings be upon him) passed near him, he heard his supplication, while the Messenger of Allah (peace and blessings be upon him) did not recognize him, and he (peace and blessings be upon him) said: "Who is this? Ask and you will be given." So Sayyiduna Abu Bakr (may Allah be pleased with him) went back to Sayyiduna Abdullah and said: What was the supplication you were making? He said: "I praised Allah and glorified Him, then I said: O Allah, there is no god but You; Your promise is true, the meeting with You is true, Your Book is true, the prophets are true, and Muhammad (peace and blessings be upon him) is true, Paradise is true, Hell is true, and Your messengers are true."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8387