Dua and Dhikr
Dua to strengthen Imaan.
1.
رَضِيتُ باللَّهِ رَبًّا، وَبِالْإِسْلَامِ دِيناً، وَبِمُحَمَّدٍ صَلَى اللَّهُ عَلِيهِ وَسَلَّمَ نَبِيَّاً. (ثلاثاً)
Radaytu billahi Rabban wa bil-Islami dinan wa bi Muhammadin nabiyyan
(I am content with Allah as my Lord, Islam as my religion and Muhammad as my Prophet)
It was narrated from Abu Salam, the servant of the Prophet (saas), that :
the Prophet (saas) said: "There is no Muslim - or no person, or slave (of Allah) - who says, in the morning and evening: 'Radaytu billahi Rabban wa bil-Islami dinan wa bi Muhammadin nabiyyan (I am content with Allah as my Lord, Islam as my religion and Muhammad as my Prophet),' but he will have a promise from Allah to make him pleased on the Day of Resurrection."
(Sunan Ibn Majah 3870)
2.
آمَنْـتُ بِاللهِ وَرُسُـلِه
Aamantu billaahi wa Rusulihi
(I believe in Allah and His Messenger.)
He also reported God’s messenger as saying, “People will continue to ask one another questions till someone says this, ‘God created all things, but who created God?’ Whoever comes across anything of that nature should say, ‘I believe in God and in His messengers.’ ” (Bukhari and Muslim.)
(Mishkat al-Masabih 66)
Narrated Ibn Umar:
Umar and a group of the companions of the Prophet (ﷺ) set out with the Prophet to Ibn Saiyad. He found him playing with some boys near the hillocks of Bani Maghala. Ibn Saiyad at that time was nearing his puberty. He did not notice (the Prophet's presence) till the Prophet (ﷺ) stroked him on the back with his hand and said, "Ibn Saiyad! Do you testify that I am Allah's Messenger (ﷺ)?" Ibn Saiyad looked at him and said, "I testify that you are the Apostle of the illiterates."
Then Ibn Saiyad asked the Prophet. "Do you testify that I am the apostle of Allah?" The Prophet (ﷺ) said to him, "I believe in Allah and His Apostles." Then the Prophet (ﷺ) said (to Ibn Saiyad). "What do you see?" Ibn Saiyad replied, "True people and false ones visit me." The Prophet said, "Your mind is confused as to this matter." The Prophet (ﷺ) added, " I have kept something (in my mind) for you." Ibn Saiyad said, "It is Ad-Dukh." The Prophet (ﷺ) said (to him), "Shame be on you! You cannot cross your limits." On that 'Umar said, "O Allah's Messenger (ﷺ)! Allow me to chop his head off." The Prophet (ﷺ) said, "If he should be him (i.e. Ad-Dajjal) then you cannot overpower him, and should he not be him, then you are not going to benefit by murdering him."
(Sahih al-Bukhari 3055)
3.
رَبَّنَا لَا تُزِغْ قُلُوْبَنَا بَعْدَ اِذْ ھَدَيْتَنَا وَھَبْ لَنَا مِنْ لَّدُنْكَ رَحْمَةً ۚ اِنَّكَ اَنْتَ الْوَھَّابُ
Rabbanaa Laa Tuzigh Quloobanaa Ba’-Da Id’hadaytanaa Wa Hab Lanaa Mil Ladunka Rah’mah Innaka Antal Wahaab
(Our Lord! Let not our hearts deviate (from the truth) after You have guided us, and grant us mercy from You. Truly, You are the Bestower.)
(Surah Al-Imran - 3:8)