One: Two stops of the last Tashahhud recitation and the sitting prayer for it ; Without these two prayers will not be valid. In the book "Jadul Mustaqani", while describing the rukun of prayer, it is said: "The last tashahhud and sitting for it". Shaykh 'Uthaymeen (may Allah be pleased with him) explained: "The last tashahhud is the tenth pillar of the prayer. The proof of this is the hadeeth of Abdullah bin Masood (may Allah be pleased with him). He said : جبرائيل وميكائيل ، السلام على فلان وفلان (Greetings to Allah from the servants. Greetings to Gabriel and Michael and salutations to such and such). Some say: Rejecting our opinion: the first tashahhud, since the first tashahhud is also tashahhud ; yet the Prophet (peace and blessings of Allaah be upon him) abandoned the first tashahhud and tried to correct this mistake by prostrating himself. The answer is : No. The main rule is that two tashahhuds are obligatory. The first tashahhud came out of this rule on the basis of Sunnah. Sahu has compensated for that through prostration. Therefore , the main provision of the last Tashahhud remained unalterable as obligatory. "Sitting for it" is the eleventh pillar of prayer. That is, stop the last meeting for Tashahhud. Suppose someone stood up straight from a prostration and stood up and recited Tashahhud. Since that person has left a rukun of prayer. That is the meeting. He must sit down and recite the Tashahhud while sitting. As he says: By "sitting for it" he associates the meeting with the tashahhud to mean that the tashahhud must be in the same meeting. Forgetting a rukun is inevitable, but it is inevitable ; Otherwise his prayer will not be pure. Shaykh 'Uthaymeen (may Allah be pleased with him) said: "The pillars are more obligatory and the pillars are more obligatory than the obligatory ones. But the pillars are different from the obligatory ones . It can be fulfilled. But the rukuns are the opposite. He further said: "The proof that the rukun is not compensated by sahu prostration is: When the Prophet (peace and blessings of Allaah be upon him) recited the two rak'ahs of the Zuhr or Asr prayer and returned the salaam, he completed the prayer and performed the sahu prostration. [Al-Sharh al-Mumti (3/315 , 323)] Therefore , the person who returned the salutation without reciting the last tashahhud , will return to the prayer if it is not too late. And sit down and recite Tashahhud and then return the salutation. Then Sahu will prostrate. Then return the salutation. And if it is too late then repeat the whole prayer. GOD is Omniscient.