A brief discussion on how Tasbih Fatima Zahra (as) transpired
There is a narration in several books such as "Man la Yahdhurhu al-faqih" that Amir al-Mu'minin Ali (as) addressed a man from Bani Sa'd and said, "I will tell this incident that happened to me and Fatima (as): Fatima (as) and I lived together. She worked hard at home doing household chores like fetching water with waterskin, grinding until his hand was sore, sweeping the house until his clothes were dusty, and working hard at cooking. Therefore, she was very tired and her clothes were blackened by the smoke of firewood. One day I told her if she went to her father, the Prophet (PBUH), and asked him to provide her with a maid she would be relieved of some of the trouble.'
Fatima went to the Prophet (PBUH) and saw people in his presence. She was shy and did not say anything to the Prophet (PBUH) and returned, but the Prophet (PBUH) realized that Fatima had come for something. The next day, the prophet (PBUH) came and said, 'O Fatima, why did you come to me yesterday?' We were afraid that if we did not say something, the Prophet (PBUH) might get up and leave, so we raised the issue and recounted to him the heavy work that Fatima (as) was doing at home which made her tired. The prophet (PBUH) replied, 'Shall I not teach you something more beneficial than a housemaid?' Then he said, 'Say "Allahu Akbar" 34 times, "Alhamdulillah" 33 times, and "Subhanallah" 33 times. Having heard that, Fatima (as) raised her head and said three times, 'We are pleased with God and the Messenger of God.'"[1]
This was the origin of the Tasbih of Hazrat Zahra (as), but due to the importance of this noble dhikr, I will mention some of the narrations about its virtue:
Hadith 1
امام صادق ـ علیه السلام ـ فرمود: "من سبح تسبیح فاطمه ـ سلام الله علیها ـ غفرالله له"[2]
Imam Sadiq ( as) says: “Whoever recite the Tasbih Fatima Zahra(as), God will forgive him”
Hadith 2
امام صادق ـ علیه السلام فرمودند: تسبیح فاطمه الزهراء ـ سلام الله علیها ـ فی دبر کل صلاه احبّ الی من صلاه الف رکعه فی کل یوم[3]
Imam Sadiq (as) says: “The Tasbih Fatima al-Zahra (as) in every prayer is more beloved to me than praying a thousand rak’ahs every day”
Hadith 3
One of the narrators says that I complained to Imam Sadiq (PBH) about the heaviness of my ear. He said: “It is upon you the Tasbih Hazrat Zahra.”[4]
References:
[1] Sheikh Saduq, Muhammad, Man la Yahdhurhu al-faqih vol. 1, p. 320.
[2] Hurr al-'Amili, Wasa'il al-Shia, Qom, published by Ahl al-Bayt Institute, 1416 AH, vol. 6, p. 439, book of Salah, chapter 7.
[3] Majlisi, Mohammad Baqir, Baharalanvar, Beirut, Nashr-e Dar-e-Ahya, 1403 AH, vol. 82, p. 332.
[4] ibid.