What is the ruling on intentionally expelling and swallowing what is between the teeth during prayer and fasting? Is it similar to saliva? Does it invalidate prayer and fasting if it is slight and has a taste? Does prayer become invalid if saliva comes out onto the lips and then returns? What is the ruling on someone who neglected to repeat a prayer, thinking it was a mere whisper (waswasah), then it became clear to him otherwise? Is he sinful for that? What is the ruling on wiping all parts of the ear during ablution (wudu')?

Intentionally expelling what is in the mouth and swallowing it invalidates fasting and prayer. As for swallowing what is between the teeth: if it is small and difficult to avoid, it does not affect fasting or prayer. But if it is considerable and can be avoided, and one swallows it intentionally, then one's fast is invalidated according to most scholars, and prayer is nullified by it.

If you feel that something impure has exited during prayer, the default is to ignore that doubt, and you are not required to repeat the prayers unless you are certain that something has exited, for doubt about purity does not invalidate it.

As for how to wipe the ears: it is by placing the inner part of the thumbs on the outer part of the earlobes, and the tips of the index fingers into the ear canals, with their middle parts meeting the inner parts, rotating them along with the thumbs.