It is narrated that the Prophet (salAllahu alayhi wasalam) said:
“Whoever believes in Allah and His Apostle (salAllahu alayhi wasalam), offers prayer perfectly and fasts the month of Ramadan will rightfully be granted Paradise by Allah, no matter whether he fights in Allah’s cause or remains in the land where he is born.”
The people said, “Oh Allah’s Apostle! Shall we acquaint the people with this good news?” He said, “Paradise has one hundred grades which Allah has reserved for the mujaahidoon who fight in His cause, and the distance between each of two grades is like the distance between the Heaven and the earth. So when you ask Allah (for something), ask for al-Firdaws which is the best and highest part of Paradise.” (the subnarrator added, “I think the Prophet (salAllahu alayhi wasalam) also said ‘Above it (alfirdaus) is the throne of the beneficent (Allah), and from its originate the rivers of Paradise.”
[Sahih al-Bukhari]