The Commander of the Faithful (AS) said: Pronounce the name of God over your ablution. (al-Istibsar, vol. 1, p. 68)
The Commander of the Faithful (AS) said: Always say "Bismillah" before performing ablution.
From Ali (AS): he was asked about a man caught in the middle of the crowd on Friday or on the day of Arafa, unable to leave the mosque because of the multitude of people, whose ablution becomes invalid. He said: Let him perform tayammum and pray with them. (al-Istibsar, vol. 1, p. 81)
The Commander of the Faithful (AS) was asked about someone whose ablution is broken in the midst of the crowd at the Friday prayer or at Arafa, and who has no possibility of leaving and renewing his ablution. He said: Let him perform tayammum (dry ablution) and pray with the congregation.
The Commander of the Faithful (AS) said: I do not care whether it was urine or water that touched me, so long as I do not know. (al-Istibsar, vol. 1, p. 180)
The Commander of the Faithful (AS) said: When I have not clearly seen that urine has splashed on me, I assume that it was water.
When Ali (AS) rose from the first two rak'as, he would say: By Your strength and Your power I stand and I sit. (al-Istibsar, vol. 1, p. 338)
When the Commander of the Faithful (AS) rose to his feet in the first and second rak'a, he would say: "Bi-hawlika wa quwwatika aqumu wa aq'ud" — By Your strength and Your power I stand and I sit.
The Commander of the Faithful (AS) said: There is no Friday prayer except in a city in which the prescribed punishments (hudud) are carried out. (al-Istibsar, vol. 1, p. 420)
The Commander of the Faithful (AS) said: It is not permissible to establish the Friday prayer except in a city where the divine punishments (hudud) are carried out.
From Abu Abdillah (AS), who said: Ali (AS) led the people in prayer without ritual purity — it was the noon prayer — and then his herald went out announcing: The Commander of the Faithful (AS) prayed without ritual purity, so repeat the prayer, and let him who is present convey this to him who is absent. (al-Istibsar, vol. 1, p. 433)
Imam al-Sadiq said: Ali (AS) prayed the noon prayer with the people, and afterwards a herald proclaimed: Ali has said that he was without ablution! So repeat your prayer, and tell those who have dispersed to repeat their prayer as well.
The Commander of the Faithful (AS) said: People perish through their bellies and their private parts, because they have not rendered us our due. But behold, our Shia and their fathers are absolved of that. (al-Istibsar, vol. 2, p. 58)
The Commander of the Faithful (AS) said: People do not pay our due out of their wealth, and yet they eat from that wealth and contract marriage with it, and so they stand exposed to perdition. For this reason we have granted a dispensation to our Shia and their fathers, so that they may be free of perdition.
The Commander of the Faithful (AS) said: There is no harm in the testimony of a bondsman, if he is just. (al-Istibsar, vol. 3, p. 15)
The Commander of the Faithful (AS) said: The testimony of someone in another's employ is accepted, provided he is just.
The Commander of the Faithful (AS) said: When a man strikes hands upon a sale, it becomes binding, even if the two parties have not yet separated. (al-Istibsar, vol. 3, p. 73)
The Commander of the Faithful (AS) said: When in a transaction the two parties shake hands with one another, the transaction becomes binding, even though they have not yet parted from each other.
The Commander of the Faithful (AS) said: Were it not for what Ibn al-Khattab did before me in this matter, none but a wretch would commit fornication. (al-Istibsar, vol. 3, p. 141)
The Commander of the Faithful (AS) said: Had Umar ibn al-Khattab not prohibited temporary marriage, none but a wretch would commit fornication.