What is the ruling on the interval between two prayers combined in the time of the second prayer?
Chapter on the Traveler's Prayer
Al-Mughni
Book of Prayer
Primary text
When combining prayers in the time of the second prayer, separation is permissible. This is because once the first prayer is performed, performing the second prayer within its allotted time does not negate the fact that the second prayer is being performed as 'Ada' (on-time performance). The soundest position confirms this, as the first prayer, once validly performed, is not invalidated by anything that occurs afterward, and the second prayer only occurs within its proper time frame.
Supporting text
There is an alternative view suggesting that sequence (mutaba'ah) is still a condition for combination because the essence of combination is joining one thing to another, which is not achieved with separation.