اللَّهُ اللَّهُ رَبِّي لا أُشْرِكُ بِهِ شَيْئًا

Allah Allah rabbi la ushriku bihi shay’an

Allah Allah is my Lord, I do not associate anything with Him

[abu Dawud, 2/87, Sahih ibn Majah 2/335]
Asma bint ‘Umayr (ra) said: “The Messenger of Allah (salAllahu alayhi wasalam) said to me: ‘Shall I not teach you some words which you can say at times of distress?
Another narration says that these words should be said 7 times.

“رَبَّنَا اكْشِفْ عَنَّا الْعَذَابَ إِنَّا مُؤْمِنُونَ “

Rabban ak-shiff ‘annal-adhaaba ‘inna mu’minoon

“Our Lord! remove from us the punishment, surely we are Believers.”
[surah ad-Dhukan; 44:12]

لا إلَهَ إِلا اللَّهُ الْعَظِيمُ الْحَلِيمُ ، لا إلَهَ إلا اللَّهُ رَبُّ الْعَرْشِ الْعَظِيمُ ، لا إلَهَ إلا اللَّهُ رَبُّ السَّموَاتِ وَ رَبُّ الأَرْضِ وَرَبُّ الْعَرْشِ الْكَرِيمُ

La ilaha ilaAllah al-‘Adheem al-Haleem, la ilaha ilaAllah Rabb al-Arsh al-‘adheem, la ilaha ilaAllah Rabb as-Samawat wa Rabb al-Ard wa Rabb al-Arsh al-Kareem

There is no god but Allah, the All-Powerful, the Forbearing; there is no god but Allah, Lord of the mighty Throne; there is no god but Allah, Lord of heaven, Lord of earth, and Lord of the noble Throne.

[Sahih al-Bukhari, 8/154, Muslim, 4/2092]
Ibn Abbas (ra) reported that when the Prophet (saws) felt distressed he would say (the above)

اللَّهُمَّ أَصْلِحْ لِي دِينِي الَّذِي هُوَ عِصْمَةُ أَمْرِي، وَأَصْلِحْ لِي دُنْيَايَ الَّتِي فِيهَا مَعَاشِي، وَأَصْلِحْ لِي آخِرَتِي الَّتِي فِيهَا مَعَادِي، وَاجْعَلِ الْحَيَاةَ زِيَادَةً لِي فِي كُلِّ خَيْرٍ، وَاجْعَلِ الْمَوْتَ رَاحَةً لِي مِنْ كُلِّ شَرٍّ

O Allah! Set right my faith which is the safeguard of my affairs. And set right for me my worldy affairs wherein is my living. And set right for me my Hereafter on which depends my after-life. And make my life for me (a source) of abundance for every good and make my death a source of comfort for me protecting me against every evil
[Muslim, 35/6565]
[Abu Hurairah (radiAllahu anhu) reported that the Messenger of Allah (salAllahu alayhi wasalam) used to say (the above)]

اللَّهُُمَّ اِنِّىْ اَسْئَلُكَ تَعْجِيْلَ عَافِيَتِكَ وَ دَفَعَ بَلآئِكَ ، وَ خُرُوْجًا مِنَ الدُّنْيَآ اِلى رَحْمَتِكَ

Allahumma inni as’aluka ta’jila ‘afiyatika wa daf’a balaika, wa khurujan min ad-dunya ila rahmatika[hadith]

 O Allah, I ask for Your haste in granting me peace, and taking me out of the trials of this world to Your Mercy
[hadith]

اللَّهُمَّ رَحْمَتَكَ أَرْجُو فَلا تَكِلْنِي إلَى نَفْسِي طَرْفَةَعَيْنٍ ، وَ أَصْلِحْلِي شَأْنِي كُلَّهُ ، لا إِلَهَ إِلَّا أَنْتَ

Allahumma rahmataka arju falaa takilni illa nafsi tarfata ‘aiinan, wa as-ih-li sha’ni kuulahu, la illaha illa anta

O Allah, I hope for Your Mercy. Do not leave me to myself even for the blinking of an eye. Correct all of my affairs for me. There is none worthy of worship but You
[Abu Dawud 4/324, Ahmad 5/42]
Supplication during times of distress and anguish

اللَّهُمَّ إِنِّي عَبْدُكَ، ابْنُ عَبْدِكَ، ابْنُ أَمَتِكَ، نَاصِيَتِي بِيَدِكَ، مَاضٍ فِيَّ حُكْمُكَ، عَدْلٌ فِيَّ قَضَاؤُكَ، أَسْأَلُكَ بِكُلِّ اسْمٍ هُوَ لَكَ سَمَّيْتَ بِهِ نَفْسَكَ، أَوْ أَنْزَلْتَهُ فِي كِتَابِكَ، أَوْ عَلَّمْتَهُ أَحَدًا مِنْ  خَلْقِكَ، أَوِ اسْتَأْثَرْتَ بِهِ فِي عِلْمِ الْغَيْبِ عِنْدَكَ، أَنْ تَجْعَلَ الْقُرْآنَ رَبِيعَ قَلْبِي، وَنُورَ صَدْرِي، وَجَلَاءَ حُزْنِي، وَذَهَابَ هَمِّي

Allahumma inni ‘abduka, ibnu ‘abdika, ibnu amatika, naasiyati biyadika, maadhin fiyya hukumuka, ‘adhlun fiyya qadha’uka asaluka bi kulli ismin huwa laka, sammaita bihi nafsaka, aw an-zaltahu fi kitabika, aw ‘allamtahu ahadan min khalqika, awista’tharta bihi fi ‘ilmil-ghaibi ‘indaka, an taj’alal-Qur’ana Rabbi’a qalbi, wa nura sadri, wa jalaa’a huzni, wa dhahaba hammi

Oh Allah, I am Your servant, the son of Your servant, the son of your maid-servant, and entirely at Your service. You hold me by my forelock. Your Decree is what controls me, and Your Commands to me are just. I beseech You by every one of Your Names, those which You use to refer to Yourself, or have revealed in Your Book, or have taught to any one of Your creation, or have chosen to keep hidden with You in the Unseen, to make the Qur’an Al-Karim the springtime of my heart, the light of my eyes, the departure of my grief, and the vanishing of my affliction and my sorrow.

[Ahmad 1:391, ibn Hibban]
The Prophet (salAllahu alayhi wasalam) said, there is no-one who is afflicted by distress and grief, and says (the above), but Allah will take away his distress and grief, and replace it with joy.” He was asked: “O Messenger of Allah, should we learn this?” He said: “Of course; everyone who hears it should learn it

اللَّهُمَّ إنِّي أعُوذُ بِكَ مِنَ الْهَمِّ وَ الْحَزَنِ ، وَ الْعَجْزِ وَ الْكَسَلِ ، وَ الْبُخْلِ وَ الْجُبْنِ ، وَ ضَلَعِ الدِّيْنِ وَ غَلَبَةِ الرِّجَالِ

Allahumma inni ‘a’udhubika minal hammi walhuzni Wal’ajzi walkasali walbukhli waljubni, Wa dal’id-daiyni wa ghalabatir-rajal

Oh Allah, I seek refuge in You from anxiety and sorrow, weakness and laziness, miserliness and cowardice, the burden of debts and from being over powered by men.

[sahih al-Bukhari 7:158, Al-Asqalani – Fath al-Bari 11:173]
said in times of worry and grief