No prayer without it

  Surat Alfatihah is the essence of the Holy Quran, and Allah has named it "Alsab' Almathani: the seven oft-repeated" in Aya (87) of Surat Alhijr because it consists of seven verses that are repeated in each rak'ah of any prayer, obligatory or supererogatory, and it has no parallel in any of the heavenly Books, where as narrated by Abu Hurayrah: "The Messenger of Allah came out to Ubayy bin Ka'b, and the Messenger of Allah said O Ubayy, and he was performing the prayer, and Ubayy turned around but he did not respond to Him, so Ubayy finished his prayer quickly, then he turned to the Messenger of Allah and said Alsalamu alaiykum: peace be upon you O Messenger of Allah! The Messenger of Allah said wa alaiykum Alslam: and peace be upon you, what prevented you from responding to Me when I called you Ubayy?, he said O Messenger of Allah I was performing the prayer, so He said Do you not find among what Allah revealed to Me Respond to Allah and to the Messenger when He calls you to what gives you life?, He said Of course, I shall not repeat that, if Allah wills, Allah's Messenger said would you like for Me to teach you a Surah the like of which has neither been revealed in the Torah, nor the Gospel, nor the Psalms, nor in the Criterion?, he said yes O Messenger of Allah! The Messenger of Allah said What do you recite in your prayer?, he said I recite Umm Alquran (Surat Alfatihah), the Messenger of Allah said by the One in whose Hand is My soul! The like of it has neither been revealed in the Torah, nor the Gospel, nor the Psalms, nor in the Criterion. It is the seven oft-repeated and the Great Quran which I was given (Jami' Altirmidhi 2875).

 Surat Alfatihah is one of the two lights which have not been given to any Prophet before Allah's Messenger Muhammad (PBUH), and one of the great favors of Allah that He has bestowed upon His Messenger (PBUH) and His Ummah is that you will never recite a letter from it for which you will not be given a reward, where as narrated by Ibn Abbas: "While Gabriel was sitting with the Messenger of Allah (PBUH), He heard a creaking sound above Him, He lifted His head and said this is a gate opened in heaven today which has never been opened before, then when an Angel descended through it, He said this is an Angel who came down to the earth who has never come down before, He greeted and said Rejoice in two lights given to You which have not been given to any Prophet before you Fatihat Alketab ''Surat Alfatihah", and the concluding verses of Surat Albaqarah, You will never recite a letter from them for which You will not be given it" (Sahih Muslim 806).

The prayer in which Surat Alfatihah is not recited is an incomplete prayer, where as narrated by Abu Hurayrah that the Messenger of Allah (PBUH) said: "If anyone observes prayer in which he does not recite Umm Alquran (Alfatihah), it is deficient and incomplete, and He repeated the word three times, it was said to Abu Hurayra at times we are behind the Imam?, he said recite it to yourself, for I have heard the Messenger of Allah (PBUH) as saying Allah Almighty says I have divided the prayer between Myself and My servant into two halves, and My servant shall have what he has asked for. So when the servant says Alhamduo le-llahi Rabbi al-alameen: Praise be to Allah, the Lord of the worlds, Allah Almighty says My servant has praised Me, and when he says: Alrahmani Alraheem: the Most Gracious, the Most Merciful, Allah says My servant has extolled Me, and when he says: Maliki yawmi eldeen: the Sovereign of the day of Judgment, Allah says My servant has glorified Me, and on one occasion He said My servant has submitted to My power, and when he says: Iyyaka na'budu wa iyyaka nasta-een: You alone we worship, and You alone we ask for help, Allah says this is between Me and My servant, and My servant shall have what he has asked for, and when he says: Ihdena alserata almustaqeem, serata allazina an'amta alaiyhim, ghaiyri elmaghduobi alaiyhim wa la al-ddalleen: Guide us to the straight path, the path of those upon whom You have bestowed Your favor, not of those who have evoked anger or of those who are astray, Allah says this is for My servant, and My servant shall have what he has asked for (Sahih Muslim 395).