743. Magrib is the time that the redness in the eastern sky appearing after sunset passes overhead.
744. Namaz of Maghrib and Isha each have special and common time:
The special time for Maghrib Namaz is from the beginning of Maghrib until the period enough for 3 Rak’at f Namaz has passed Maghrib. So, if one is passenger and offers all Isha Namaz, unintentionally in this time, his prayer is void. And the special time for Isha In normal circumstances is the time when only period enough to offer Isha Namaz is left before mid-night and if one does not offer his Maghrib prayer intentionally, he/she must first offer Isha Namaz and after that the Maghrib Namaz.
And between the special time of Maghirb and special time of Isha, is their common time and if a person offers Isha, unintentionally, before the Maghrib and later he understands that, his prayer is in order, and he/she should offer Maghrib Namaz after that.
748. If a person in normal circumstances does not offer Isha prayers till after midnight, he should, as a recommendedy precaution, offer the prayers in question before the dawn prayers, without making a Niyyat of Ada (i.e. in time) or Qadha (i.e. after the lapse of time).