Musannaf Ibn Abi Shaybah

Hazrat Abu Saeed Khudri narrates that he was once with the Noble Prophet (peace and blessings be upon him). When the Prophet entered the mosque, he saw a man sitting in the middle of the mosque cracking his fingers and talking to himself. The Prophet signaled to him to stop, but he did not understand. Then the Prophet (peace and blessings be upon him) turned towards Hazrat Abu Saeed Khudri and said: When any of you performs prayer, he should not crack his fingers. For intertwining the fingers is from Satan. You remain in prayer as long as you are in the mosque.

Hazrat Saeed bin Musayyib narrates that the Noble Prophet (peace and blessings be upon him) said: When any one of you is in the mosque, he should not intertwine his fingers with each other.

Hazrat Abu Thamamah Qamah says that at the place of Balat, I met Hazrat Ka'b. I interlaced my fingers, so he struck my hand forcefully and said that we have been forbidden from cracking our fingers in prayer. I said to him, "May Allah have mercy on you! Are you seeing me in prayer?" He said, "Whoever performs ablution and sets out with the intention of prayer is considered to be in prayer."

Hazrat Nu’man bin Abi ‘Ayyash narrates that the predecessors used to prohibit cracking fingers during prayer.

Ibrahim has considered cracking the fingers during prayer to be disliked.