My question is, when a person has a need to yawn or sneeze, it is best practice to say Alhamdulillah. If a person is praying however should they Alhamdulillah during the prayer then continue praying or say it once they have finished praying?

Saying Alhamdu Lillah is permissible when sneezing whether in prayer or
When yawning , there isn’t anything prescribed to be said.

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