Angels come to people in succession by night and day
9-1-2014 | IslamWeb
Question:
Are angels fallible or infallible? Will they be punished if they make a mistake? Do the angels to the right and left remain with everyone permanently during his lifetime or do they change every specific time?
What is the best book in which I can find further information about angels? May Allaah Reward you.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Angels were created to worship and obey Allaah The Almighty, and to submit completely to His commands. Therefore, they are infallible. Allaah The Almighty Says (what means):
· {They do not disobey Allaah in what He Commands them but do what they are commanded.} [Quran 66:6]
· {And those near Him are not prevented by arrogance from His worship, nor do they tire.} [Quran 21:19]
· {Then those who are near your Lord exalt Him by night and by day, and they do not become weary.} [Quran 41:38]
· {[Who] Made the angels messengers } [Quran 35:1]
The angels on the right and on the left are the guardian angels assigned to write the deeds of people. It is this kind of angel that is meant in the verse in which Allaah The Almighty Says (what means):
· {And indeed, [appointed] over you are keepers, noble and recording} [Quran 82:10-11]
· {When the two receivers receive, seated on the right and on the left.} [Quran 50: 17]
Ibn Jurayj 
said, “They are two angels. One of them on the right of every slave to record the good deeds and the other on the left to record the evil deeds. They come to people in succession by night and day.” It was narrated on the authority of Abu Hurayrah 
that the Prophet, sallallaahu ‘alayhi wa sallam, said: “Angels come to you in succession by night and day and all of them get together at the time of the Fajr and ‘Asr Prayers. Those who passed the night with you (or stayed with you) ascend (to Heaven) and Allaah Asks them, though He Knows best, ‘In what state did you leave My slaves?’ The angels reply, ‘When we left them they were praying and when we reached them, they were praying.’” [Al-Bukhari and Muslim]
Ibn Zamneen narrated in his book As-Sunnah that Al-Hasan said, “The guardian angels who take turns guarding each slave are four; two by night and two by day. They gather together every day at the time of the Fajr Prayer.”
Ibn Hibbaan, may Allaah Have mercy upon him, said, “This narration gives a clear-cut indication that the guardian angels of the night descend to people at the time of the ‘Asr Prayer in which the angels of the day ascend to heaven.”
Ibn Jareer narrated that Ibn ‘Abbaas said, “Allaah Appointed guardian angels who take turns guarding each slave, some by night and some by day. They also record the deeds of everyone.”
According to what has been mentioned above, we come to know that the angels of the night are other than the angels of the day. An-Nawawi said, “‘Iyaadh said, ‘The predominant opinion in this regard is that these angels are the guardian angels.’”
Allaah Knows best.