There is an authentic hadith which says:
The Messenger of Allah (may peace be upon him) observed the noon and afternoon prayers together, and the sunset and Isha' prayers together without being in a state of fear or in a state of journey.
Sahih Muslim 705 a
Yet despite this text, there are some who say combining the prayers in such a way unless there is a pressing hardship is not permissible.
Does anyone know the evidence for such a position? It would seem from the hadith that combining is permissible as long as there is a valid reason for it (such as you are working during the day or in school and cannot take time off till you reach home at 'Asr time).
Also a related question, is combining the prayers in such a way (Zurh with Asr and Maghrib with Isha, 4 and 4, 4 and 3) what the Shia do and is their evidence the same as this hadith?
I think this is a different question than Combine Zuhr and Asr when late for Zuhr?, because none of the answers there provide an evidence for saying combining is not permissible (there is only one hadith quoted which is very weak).