Musannaf Ibn Abi Shaybah

Hazrat Bara bin Azib narrates that in the verse of the Holy Qur'an { یُثَبِّتُ اللّٰہُ الَّذِیْنَ اٰمَنُوْا بِالْقَوْلِ الثَّابِتِ فِی الْحَیٰوۃِ الدُّنْیَا }, steadfastness in the life of this world means that when two angels come to a person in the grave, they ask him, "Who is your Lord?" He says, "My Lord is Allah." They ask, "What is your religion?" He says, "My religion is Islam." They ask, "Who is your Prophet?" He says, "My Prophet is Muhammad (peace and blessings be upon him)." This is steadfastness in the life of this world.