In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Shaikh Rabee Bin Haadi Al-Madkhali [hafidhahullaah] was asked about the hadeeth: “Whoever prays for forty days in congregation and catches the first Takbeer, two affairs will be written for him- safety from the Fire and hypocrisy”. [Tirmidhee 241. Graded Hasan by Imaam Albaani (rahimahullaah)]
Shaikh Rabee [hafidhahullaah] said: We ask Allaah to enable all of us accomplish this. This is a difficult affair that requires striving against the Nafs and an intense desire to accomplish this deed. We will not accomplish this except if we are early for every prayer, and the A’dhaan is not called except that we are in the vicinity of the masjid or in it. This [person] will accomplish it by the Will of Allaah. Therefore, be eager for this good deed.
[Source: http://www.rabee.net/ar/questions.php?cat=42&id=539 slightly paraphrased]