Maulana Ali (AS) has said: “He who speaks during prayer should say it afresh.” This means that the speech which is permitted in the namaaz does not render it null and void. If something is uttered other than the supplication prescribed in the namaaz then surely it should be performed afresh.

Imaam Mohammad Ul-Baaqir (AS) has said: ‘The words addressed by a man to Allaah during namaaz (ritual prayer) do not constitute speech.' Therefore anything that is spoken except, the declaration of greatness of Allaah (takbeer) ; the recitation of the Qur'an (qeraat) ; the glorification of Allaah (tasbeeh) ; the giving of praise to Allaah (tahmeed) ; bearing witness to Allaah and Rasoolullaah (SAWS) (tashahhud) ;supplication to Allaah (du'a) ; invalidates the prayer.

Maulana Ali (AS) has said: ‘A man approached Rasoolullaah (SAWS) during the very first ‘umrah he was performing, and saluted (saying of the assalaamo alaykum ) him while Rasoolullaah (SAWS) was praying. Rasoolullaah (SAWS) did not answer to him. When he completed his prayer and was about to go away, Rasoolullaah (SAWS) asked, “Where is the man who saluted me a little while ago? I was praying and the angel Jibraeel (Gabriel) came to me and said: Prevent your community to return salutation while praying.'”

It is permitted to indicate a desire to reply by saying Subhaan Allaah, if the necessity arises and there is no escape but to fulfill the need. If you are in need of something while in state of prayer, then you should say Subhaan Allaah or point to it with the finger . In case of woman in similar circumstances, she may clap her hands gently without turning the face from Qiblah.

Imaam Ja'far us-Saadiq (AS) has said: ‘He who laughs during prayer, renders it void, but a mere smile does not nullify it.' To preserve the magnitude of prayer it is better neither to smile nor to pay attention to anyone, nor to engage in any other matter, for this will be more meritorious and safer for the person who is praying.

Rasoolullaah (SAWS) forbade the worshipper ( ‘ebaadatguzaar ) to blow from his mouth during prayer. He prohibited the blowing of breath at the place of prostration; however, such an act does not render the prayer invalid.

Rasoolullaah (SAWS) has said: “Allaah dislikes six actions: playfulness during prayer (either with beard or clothes or rosary); expectation of gratitude in charity; coarse speech while fasting; laughter in the cemetery ( qabarastaan ); looking into privacy of another's house without his permission; and sitting in the mosque while in a state of major ritual impurity.”

Imaam Ja'far us-Saadiq (AS) has said: A person is allowed to rub the spot where he feels itching sensation during prayer; but he forbade cracking the knuckles (tanqeed) intentionally during prayers, and this means bending the fingers from their joints so that they make crackling sound.

He also said that if an insect were to bite a man during prayers, he may throw it away. He was asked what a man should do if he were to find a serpent or scorpion or any harmful animal during prayer which poses a threat to his life, and he said that the man should kill it. Thereafter he should begin his prayer afresh.

Imaam Mohammad ul-Baaqir (AS) has said: “Do not turn your face from the Qiblah (place of prostration) during prayers lest the prayers be void. Show your fear by your eyes and do not raise them towards the sky; but let your sight be engaged to the place of prostration.” Imaam Ja'far us-Saadiq (AS) has said: “He who loses his attention in prayer ceases to pray.”

Rasoolullaah (SAWS) once entered the mosque and saw Anas bin Maalik looking around while praying. So Rasoolullaah (SAWS) said: ‘O Anas, worship as if you are saying farewell, believing that this was the very last of your prayers. Engage your eyes to the place of prostration. Care not for him who is on your right or on your left. Know only that you are before Allaah Who beholds you while you cannot behold Him.'

Imaam Ja'far us-Saadiq (AS) has said that a man who happens to look at a Qur'an or book while praying renders it void. He forbade playing with the ring or looking at its engraving during prayers. Rasoolullaah (SAWS) saw a man playing with his beard during prayer, and he said: ‘Behold! If the fellow had fear in his heart, his limbs would have mirrored it.' You should not play with your hair, ring, ornaments, buttons of your dress, beard, or rosary during prayers. You should not indulge in making gestures with your fingers or arranging your dress properly, that might divert your attention from prayer. Any such thing that is committed will make the prayer void.

Imaam Ja'far as-Saadiq (AS) disliked that the face be veiled during prayers unless there was a valid reason for it. He forbade the closure of the eyes during prayers.

Maulana Ali (AS) was asked about some living creature crossing in front of the worshipper. He said: “Nothing causes the discontinuance of prayer. But do not allow crossing anyone in front of you, even if you have to use force!” Maulana Ali (AS) said: ‘It came to pass that once Rasoolullaah (SAWS) was praying and a dog passed in front of him, then a donkey, and then a woman, but he continued to pray. When he finished praying, he said: “I saw what you saw; the prayer of faithful, however, is not terminated by such events. Nevertheless, prevent such events as far as you can.”'

Maulana Ali (AS) has said: ‘Rasoolullaah (SAWS) has warned us against the habit of yawning excessively during prayers; surely, it is the disorderly cry of Shaitaan . Allaah is very pleased with the act of sneezing, but dislikes yawning during prayers.'

Imaam Ja'far us-Saadiq (AS) disapproved the act of yawning and stretching during prayers, for they clearly indicate a state of laziness. Therefore, both their practice and their repetition are prohibited. Yawning is an unintentional act; thus he who yawns and cannot control it, should place his hand over his mouth and then return it to its normal position.

Maulana Ali (AS) said: If Rasoolullaah (SAWS) happened to yawn during prayers; he would put his right hand to his mouth. The act of sneezing, however, generally indicates health and is therefore approved. It is desirable when sneezing during prayers to control as far as possible and not sneeze loudly.

Maulana Ali (AS) has said: ‘When anyone of you happens to sneeze during prayers, let him do so as gently as a cat.' If one happens to sneeze while praying, he should praise Allaah and send salawaat to Rasoolullaah (SAWS) secretly in his heart.