Shaykh al-Islām Ahmad ibn Taymiyyah—may Allah have mercy on him—was asked:

For someone seeking to worship Allah, it may be unclear which practice is preferable in the following matters I shall mention, on which the imams have differed:

In prayers with audible recitation, which is preferable: refraining from reciting the basmalah (“In the name of Allah, the Most Compassionate, the Most Merciful”) aloud, or reciting it aloud?

Which is preferable: regularly offering the qunūt supplication in the dawn prayer, omitting it, or offering it occasionally when beneficial? The same question applies to the witr prayer.

Which is preferable: prolonging the prayer while keeping its parts proportionate in duration and manner, or shortening it according to what people have become accustomed to in these times?

When shortening prayers during travel, which is preferable: regularly combining them, or doing so occasionally as needed?

Is spending the entire night in prayer an innovation or a sunnah? Or is praying for part of the night better than praying throughout it?

Likewise, is fasting on consecutive days preferable, or fasting some days and not others? And what of continuing a fast without breaking it at night?

Is habitually wearing coarse clothing and eating coarse food preferable or not?

Which is preferable during travel: performing the regular sunnah prayers, omitting them, or performing some but not others? The same question applies to other voluntary prayers during travel.

Which is preferable during travel: fasting or not fasting?

And if someone cannot find water, or cannot use it because of illness, or fears harm from using it because of severe cold or the like,