بسم الله الرحمن الرحيم
We begin with Allah’s blessed name, we praise him and we glorify him, seek his forgiveness and ask him to guide us. Whoever Allah guides, None can lead astray and whoever he misguides, None can guide. There is no power and no strength except from Allah, The most high, the Most great, the most powerful. We bear witness that there is no one worthy of worship but Allah Alone, and we bear witness that Prophet Muhammad (pbuh) is His slave-servant and the seal of His Messengers. We pray for peace and blessings on all the noble messengers and in particular on the last of them all “the blessed prophet Mohammad (pbuh)”
I think by Dua-Masura you mean the dua that is recited in last tashahud of the prayer. I.e. after tahiya and darood but before ‘Tasleems’.
It is preferred for the person to supplicate after the final tashahud and before making the final salutations (that end the prayer). The person may ask for whatever he wishes of the good of this life and the hereafter. Supplications are preferred acts in general, regardless of whether they are reported from the Prophet or not, although supplications authenticated by the sunnah are better.
There are many different supplications before the 'tasleems', recorded in the authentic Sunnah of our beloved prophet (pbuh). The one mentioned here:
Narrated 'Abdullah bin 'Amr: Abu Bakr As-Siddiq said to the Prophet, "Teach me an invocation with which I may invoke (Allah) in my prayer." The Prophet said, "Say: Allahumma inni zalamtu nafsi zulman kathiran wala yaghfirudh-dhunuba illa anta, Faghfirli maghfiratan min indika war-hamni, innaka antalGhafur-Rahim." SAHIH AL-BUKHARI[Vol.: 8 :: Book: 75 :: Hadith: 338]
I ask Allah to make this a sincere effort, seeking his pleasure, and I ask him to grant us refuge in him from the evils within ourselves, and that in our deeds. I ask him to grant us success in achieving whatever pleases him; And May Allah Shower His blessings and mercy upon our beloved Prophet Muhammad (pbuh), his family and his Companions and on all those who follow him until the final hour.Ask Your Question