First of all, it should be clear that offering Supererogatory Prayers is one of the effective means that brings man close to Allah. So, true servants of Allah are always keen to offer Supererogatory Prayers, not alone the option ones.
There’s controversy among scholars on Salatu-Tasbih This will be clarified in the following:
Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
“Salatul-tasbih is a highly controversial form of Salah. While considered by some to be a Nafl entailing great blessings, many scholars consider it as weak, dubious, and, therefore, not worthy of consideration.
Those who uphold and advocate the benefits of this Salah have based their view on the following Hadith attributed to the Prophet, peace and blessings be on him:
“The Prophet, peace and blessings be upon him, said to his uncle `Abbas: “O `Abbas, my dear uncle, shall I give you, shall I gift you, shall I bestow on you ten special gifts. If you do what I am going to tell you shortly, you will gain the following ten benefits: Allah will forgive all your sins: both the first and the last, the old and the new, the conscious ones as well as the unconscious, the small and the big, the private and the public – ten things altogether. You should perform four Rak`ahs (of Salah), and in the first Rak`ah you should read Fatihah and a Surah. After having done so, while still standing, read the following:
“Subhaana Allah, waal-hamdu lillaah, walaa ilaaha illa Allaah, wa Allaahu akbar” 15 times, then you go to Ruku` and recite the above again 10 times, then lift your head up from Ruku` and say, while standing, the same words 10 times, then, go to Sujud and say the same 10 times, then, rise from Sujud and while sitting say it again 10 times.
Afterwards, you should go back to Sujud again, and say the same words 10 times, then, raise your head from Sujud and, again, say the same 10 times: It adds up to a total of 75 Tashbihs in each Rak`ah. You must do the same in each of the four Rak`ahs. If you can do it once in every Jumu`ah do so; if you cannot, then do it once a month, if you cannot, do it once a year, if you cannot, do it once in your life-time at least.” (Reported by Abu Dawud)
The above report is not to be found in the Sahih of Bukhari or the Sahih Muslim or the Muwatta’ of Imam Malik. It had been unknown to the great Imams such as Malik, Abu Hanifah and, presumably, to Imam Shafi`i, and it was considered strange and unworthy of consideration by Imam Ahmad.
The above Hadith is listed among the fabricated Hadiths by Ibn Al-Jawzi. According to Imam Ibn Hajar: “All of the chains of this Hadith are weak” Also, “It is contrary to the prescribed format of Prayer.” Ibn Hajar further added, “It had been declared as weak by both Ibn Taymiyyah and Al-Mizzi.” In the words of Ibn Al-`Arabi, “There is not a single authentic or sound Hadith on it.” Imam Nawawi has also joined the ranks of scholars questioning the nature of the report as well as the strange format of Salatul-Tasbih, and hence, considering it as unworthy of consideration.
In light of the above, it is only reasonable to state there is no authentic evidence to recommend the practice of Salatul-Tasbih. Besides, we have sufficiency in what has been authentically transmitted from the Prophet, peace and blessings be on him, and accepted by the Ummah at large – such as Salatul-Al-Hajah, Salatul-Istikharah, Salatul-Tawbah, etc, and thus we do not need to resort to such a highly contentious form of Salah. Moreover, we believe that the Prophet, peace and blessings be on him, has conveyed to us plainly and clearly everything we ought to do in this religion of Islam.”