Sahih al-Bukhari Book 9, Hadith 50
My father said, "Allah's Messenger (ﷺ) said, 'Whoever prays the two cool prayers (`Asr and Fajr) will go to
Paradise.' "
We were with the Prophet (ﷺ) on a full moon night. He looked at the moon and said, "You will certainly see your Lord as you see this moon, and there will be no trouble in seeing Him. So if you can avoid missing (through sleep, business, etc.) a prayer before the rising of the sun (Fajr) and before its setting (`Asr) you must do so. He (the Prophet (ﷺ) ) then recited the following verse: And celebrate the praises Of Your Lord before The rising of the sun And before (its) setting." (50.39)
Zaid bin Thabit said, "We took the "Suhur" (the meal taken before dawn while fasting is observed) with the Prophet (ﷺ) and then stood up for the (morning) prayer." I asked him how long the interval between the two (Suhur and prayer) was. He replied, 'The interval between the two was just sufficient to recite fifty to Sixth 'Ayat."