Then he (sallallaahu 'alaihi wa sallam) would commence the prayer by saying:
Allaah is the Greatest141;
he ordered "the man who prayed badly" to do likewise as has been mentioned, and he said to him: Verily, the prayer of a person is not complete until he has made an ablution which has included the necessary parts of the body and has then said: 'Allaahu Akbar'.142
He would also used to say: The key to the prayer is purification, it is entered by takbeer and exited by tasleem.143
Also, "he used to raise his voice for the takbeer such that those behind him could hear."144 But, "when he fell ill Abu Bakr used to raise his voice to convey the takbeer of the Messenger (sallallaahu 'alaihi wa sallam) to the people."145
He would also say: When the Imaam says: Allaahu Akbar, then say: Allaahu Akbar.146
He would raise his hands sometimes with the takbeer,147 sometimes after the takbeer,148 and sometimes before it.149
"He would raise them with fingers apart [not spaced out, nor together]",150 and "he would put them level with his shoulders"151, although occasionally, "he would raise them until they were level with [the tops of] his ears."152
"He (sallallaahu 'alaihi wa sallam) used to place his right arm on his left arm"153, and he used to say: We, the company of prophets, have been commanded to hasten the breaking of the fast, to delay the meal before the fast, and to place our right arms on our left arms during prayer.154
Also "he passed by a man who was praying and had placed his left arm on his right, so he pulled them apart and placed the right on the left."155
"He used to place the right arm on the back of his left palm, wrist and forearm"156, "and he commanded his companions to do likewise"157, and (sometimes) "he would grasp his left arm with his right."158
"He used to place them on his chest."159
Also "he used to forbid putting one's hand on the waist during prayer [and he put his hand on his waist (to demonstrate)]"160. And this is the "silb" which he used to forbid.161
"He (sallallaahu 'alaihi wa sallam) used to incline his head during prayer and fix his sight towards the ground"162 - "while he was in the Ka'bah, his sight did not leave the place of his prostration until he came out from it"163; and he said, It is not fitting that there should be anything in the House which disturbs the person praying.164
"He used to forbid looking up at the sky"165, and he emphasised this prohibition so much that he said: People must refrain from looking up at the sky in prayer, or their sight will not return to them (and in one narration: or their sight will be plucked away).166
In another hadeeth: So when you pray, do not look here and there, for Allaah sets His Face for the face of his slave in his prayer as long as he does not look away"167, and he also said about looking here and there, "it is a snatching away which the devil steals from the slave during prayer.168
He (sallallaahu 'alaihi wa sallam) also said: Allaah does not cease to turn to a slave in his prayer as long as he is not looking around; when he turns his face away, Allaah turns away from him169; he "forbade three things: pecking like a hen, squatting (iq'aa'), like a dog and looking around like a fox"170; he also used to say, Pray a farewell prayer as if you see Him, but if you do not see Him, surely He sees you171; and, Any person who, when an obligatory prayer is due, excels in its ablution, humility and bowings, will have it as a remission for his previous minor sins as long as he does not commit a major sin, and this (opportunity) is for all times.172
Once he (sallallaahu 'alaihi wa sallam), prayed in a khameesah173 and (during the prayer) he looked at its marks. So when he finished, he said: Take this khameesah of mine to Abu Jahm and bring me his anbijaaniyyah174, for it has diverted my attention from the prayer (in one narration: for I have looked at its marks during the prayer and it almost put me to trial).175 Also "'Aaishah had a cloth with pictures spread towards a sahwah176, towards which the Prophet (sallallaahu 'alaihi wa sallam) prayed and then said: Take it away from me [for its pictures did not cease to thwart me in my prayer].177
He would also say: Prayer is not valid when the food has been served, nor when it is time to relieve oneself of the two filths.178