It is a Sunnah.

is it mandatory or is it a sunnah to insert either index finger of one the hands in the ear or any other finger in the ear while reciting azaan?

Prayer | August 9, 2015 8:20 pm
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during salah sometimes i clasp my left wrist with the right hand, is it permissible. i do both, sometimes i place my right hand on left with my five fingers placed on left forearm and sometimes i simply make a firm grip on my left wrist not placing the right hand but rather holding the left wrist tightly with my right hand.
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There were two calls for salaat ul-fajr (prayer the first just before dawn—for those who are awake performing night prayers so as for them to either rest for Fajr or have food if they intend to fast the next day, and for those who are asleep in order they may begin to arise and be ready for Fajr. Sheikh, it means after first call of adhan we should stop praying tahajud & take rest?