The Prophet, sallallaahu ‘alayhi wa sallam, said:
“Whoever performs the [obligatory] prayers for [the sake of] Allaah for forty days with the congregation, catching the first Takbeer [Allaahu Akbar], he will be recorded as being free from two things: free from the Fire and free from hypocrisy.”
(At-Tirmithi (241); Al-Albaani ruled it as sound (Hasan))