Answer
In the Name of Allah, Most Gracious, Most Merciful. All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- You must never hesitate in performing Zhuhr before proceeding to your next class; you are allowed to postpone it only if you are certain that you can safely catch Zhuhr after your class.
2- If you do not get any time at all (i.e. not even five minutes of break between the two classes), then of course in such a circumstance, you are allowed to combine Zhuhr and Asr.
Responding to your question, Sheikh Ahmad Kutty, a senior lecturer and Muslim scholar at the Islamic Institute of Toronto, Canada, states:
While fully understanding your predicament, I must say: since Prayer is the most important work we can do in this world, and since its time has been appointed and fixed by Allah, it is important for us to strive to do it even if we were allowed only five minutes’ break.
Islam, however, teaches us that in circumstances such as the one you have described, we are certainly allowed to do the absolute minimum obligatory Prayer, which in the case of Zhuhr is four rakahs of fard; it can very well be done in a matter of five minutes.
So you must never hesitate in performing Zhuhr before proceeding to your next class; you are allowed to postpone it only if you are certain that you can safely catch Zhuhr after your class.
If, on the other hand, Allah forbids, you do not get any time at all (i.e. not even five minutes of break between the two classes), then of course in such a circumstance, you are allowed to combine Zhuhr and Asr as you have mentioned, according to some authentic scholars.
They have based it on the authentic report which has been narrated on the authority of Ibn Abbas (may Allah be pleased with him); according to him, the Prophet (peace and blessings be upon him) had combined prayers in this way in order to indicate that his community can do so when they are faced with difficult situations; the situation you have mentioned definitely falls in this category only if you can’t even get five minutes’ break.
It should be comforting for you to know that in exceptional circumstances (like that of yours) you can skip sunan (recommended) and nawafil (optional) prayers that come either before or after obligatory prayers without incurring any blame; for obligatory prayer is the absolute minimum we are required to do at all times, and we must never be neglectful in performing it. Sunan and nawafil, however, can be skipped or postponed sometimes, while we should always be keen in performing them in ordinary times.
Almighty Allah knows best. Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.