The dua for supplication at the start of the prayer (salah) is an emphatic and comforting way of asking Allah (سُبْحَانَهُ وَتَعَالَى) for His blessings and pacifying one's heart in hopes of a great reward from Allah. In hadith, 6 different duas have been recited at the start of prayer by the Prophet Muhammad (ﷺ) on different occasions, and any one of them can be recited by a believer.
Hisnul Muslim, a well-known dua book, has compiled various authentic supplications said by the Prophet Muhammad (ﷺ) at the start of the prayer. In the dua, the believer asks Allah (سُبْحَانَهُ وَتَعَالَى) to wipe clean his sins and send them apart from his body like the east and west (Sahih al-Bukhari 744). The same has been reported by Abu Hurairah (رَضِيَ ٱللَّٰهُ عَنْهُ) in (Sahih Muslim 598 a-b), (Sunan an-Nasa'i 895), and (Sunan Ibn Majah 805).
In another dua for supplication at the start of the prayer, the reciter praises the glory and omnipotence of Allah (سُبْحَانَهُ وَتَعَالَى) (Sunan Ibn Majah, Hadith 806). Abu Sa'eed (رَضِيَ ٱللَّٰهُ عَنْهُ) reported the same in (Sunan an-Nasa'i 900). In another extensive dua, the reciter praises the unparalleled attributes of Allah (سُبْحَانَهُ وَتَعَالَى) in addition to asking Him for guidance towards the right path (Sunan an-Nasa'i 1625), (Jami` at-Tirmidhi 3420). 'Abd al-Rahman b. 'Auf (رَضِيَ ٱللَّٰهُ عَنْهُ) reported the same dua in (Sahih Muslim 770).
Prayer Duas
Allaahumma baa'id baynee wa bayna khataayaaya kamaa baa'adta baynal-mashriqi walmaghribi, Allaahumma naqqinee min khataayaaya kamaa yunaqqath-thawbul-'abyadhu minad-danasi, Allaahum-maghsilnee min khataayaaya, bith-thalji walmaa'i walbarad.
O Allah, separate me from my sins as You have separated the East from the West. O Allah, cleanse me of my transgressions as the white garment is cleansed of stains. O Allah, wash away my sins with ice and water and frost.
Subhaanaka Allaahumma wa bihamdika, wa tabaarakasmuka, wa ta'aalaa jadduka, wa laa 'ilaaha ghayruka.
Glory is to You O Allah, and praise. Blessed is Your Name and Exalted is Your Majesty. There is none worthy of worship but You.
Wajjahtu wajhiya lillathee fataras-samawati wal-arda haneefan wama ana minal-mushrikeen, inna salatee wanusukee wamahyaya wamamatee lillahi rabbil-AAalameen, la shareeka lahu wabithalika omirtu wa-ana minal-muslimeen. Allahumma antal-maliku la ilaha illa ant. anta rabbee wa-ana AAabduk, thalamtu nafsee waAAtaraftu bithanbee faghfir lee thunoobee jameeAAan innahu la yaghfiruth-thunooba illa ant.wahdinee li-ahsanil-akhlaqi la yahdee li-ahsaniha illa ant, wasrif AAannee sayyi-aha la yasrifu AAannee sayyi-aha illa ant, labbayka wasaAAdayk,walkhayru kulluhu biyadayk, washsharru laysa ilayk, ana bika wa-ilayk, tabarakta wataAAalayt, astaghfiruka wa-atoobu ilayk.
I have turned my face sincerely towards He who has brought forth the heavens and the Earth and I am not of those who associate (others with Allah). Indeed my prayer, my sacrifice, my life and my death are for Allah, Lord of the worlds, no partner has He, with this I am commanded and I am of the Muslims. O Allah, You are the Sovereign, none has the right to be worshiped except You. You are my Lord and I am Your servant, I have wronged my own soul and have acknowledged my sin, so forgive me all my sins for no one forgives sins except You. Guide me to the best of characters for none can guide to it other than You, and deliver me from the worst of characters for none can deliver me from it other than You. Here I am, in answer to Your call, happy to serve you. All good is within Your hands and evil does not stem from You. I exist by your will and will return to you. Blessed and High are You, I seek Your forgiveness and repent unto You.
Allahumma rabba jibra-eel, wameeka-eel, wa-israfeel fatiras-samawati walard, AAalimal-ghaybi washshahadah, anta tahkumu bayna AAibadika feema kanoo feehi yakhtalifoon. ihdinee limakh-tulifa feehi minal-haqqi bi-ithnik, innaka tahdee man tasha-o ila siratin mustaqeem.
O Allah, Lord of Jibraeel, Meekaeel and Israfeel (great angles), Creator of the heavens and the Earth, Knower of the seen and the unseen. You are the arbitrator between Your servants in that which they have disputed. Guide me to the truth by Your leave, in that which they have differed, for verily You guide whom You will to a straight path.
Allaahu 'Akbar Kabeera, Allaahu 'Akbar Kabeera, Allaahu 'Akbar Kabeera, walhamdu lillaahi katheera, walhamdu lillaahi katheera, walhamdu lillaahi katheera, wa Subhaanallaahi bukratan wa'aseela.(1)'A 'oothu billaahi minash-Shaytaan: min nafkhihi, wa nafthihi, wa hamzihi.(2)
Allah is the Greatest, Most Great. Allah is the Greatest, Most Great. Allah is the Greatest, Most Great. Praise is to Allah, abundantly. Praise is to Allah, abundantly. Praise is to Allah, abundantly. Glory is to Allah, at the break of day and at its end. (Three times)(1)I seek refuge in Allah from Satan. From his breath and from his voice and from his whisper.(2)
Allahumma lakal-hamdu 'Anta noon samaawaati wal'ardhi wa man feehinna, wa lakal-hamdu 'Anta qayyimus-samaawaati wal'ardhi wa man feehinna, wa lakal-hamdu 'Anta Rabbus-samaawaati wal'ardhi wa man feehinna wa lakal-hamdu laka mulkus-samaawaati wal'ardhi wa man feehinna wa lakal-hamdu 'Anta Malikus-samaawaati wal'ardhi wa lakal-hamdu 'Antal-haqq, wa wa'dukal-haqq, wa qawlukal-haqq wa liqaa'ukal-haqq, waljannatu haqq, wannaaru haqq, wannabiyy oona haqq, wa Muhammadun haqq, wassaa'atu haqq Allaahumma laka 'aslamtu, wa 'alayka tawakkaltu, wa bika 'aamantu, wa 'ilayka 'anabtu, wa bika khaasamtu, wa 'ilayka haakamtu. Faghfir lee maa qaddamtu, wa maa 'akhkhartu, wa maa 'asrartu, wa maa 'a'lantu 'Antal-Muqaddimu, wa 'Antal-Mu'akhkhiru laa 'ilaaha 'illaa 'Anta 'Anta 'ilaahee laa 'ilaaha 'illaa 'Anta.
O Allah, praise is to You. You are the Light of the heavens and the earth and all that they contain. Praise is to You, You are the Sustainer of the heavens and the earth and all they contain. Praise is to You, You are the Lord of the heavens and the earth and all they contain. Praise is to You, Yours is dominion of the heavens and the earth and all they contain. Praise is to You, You are the King of the heavens and the earth. And praise is to You. You are the Truth, Your Promise is true, Your Word is true, Your audience is true, Paradise is true, Hell is true, the Prophets are true, and Muhammad (peace and blessings be upon him) is true, and the Hour of Judgment is true. O Allah, to You I have submitted, and upon You I depend. I have believed in You and to You I turn in repentance. For Your sake I dispute and by Your standard I judge. Forgive me what I have sent before me and what I have left behind me, what I have concealed and what I have declared. You are the One Who sends forth and You are the One Who delays , there is none who has the right to be worshiped but You. You are my God, there is none who has the right to be worshiped but You.
The Prophet Muhammad (ﷺ) would usually fall silent before reciting the dua, thereby directing all his concentration toward what he was saying and what that meant for him. These duas should be recited with the utmost attention and a stern belief that what one is reciting is completely true. One should also recite the duas with total hope that Allah (سُبْحَانَهُ وَتَعَالَى) will grant them whatever, if it is good for them, is asked of Him.
By far, the greatest benefit of dua for supplication at the start of the prayer is emphasizing and acknowledging the sovereignty and greatness of Allah (سُبْحَانَهُ وَتَعَالَى). The dua helps beseech Allah to forgive our sins and wipe us clean like a white cloth that's been washed. The duas are also a means of reminding ourselves of the weakness of man and his total dependence on Allah (سُبْحَانَهُ وَتَعَالَى). The dua for supplication at the start of the prayer is an excellent method of asking Allah (سُبْحَانَهُ وَتَعَالَى) for His guidance and help.