How to Be Free of Fears and Insecurities
Imām Ibn Taimiyyah, may Allāh have mercy on him, said:
Whenever tawḥīd [singling Allāh out in worship and all that is for Him alone] gets stronger in the heart of a slave [of Allāh], [so too] does his īmān [faith through belief, speech, and actions], his feeling of security and serenity in his heart, his placement of trust and reliance [upon Allāh], and his having certainty.
The fear that occurs in people’s hearts is the shirk¹ that is in their hearts. Allāh the All-High says:
سَنُلۡقِی فِی قُلُوبِ ٱلَّذِینَ كَفَرُوا۟ ٱلرُّعۡبَ بِمَاۤ أَشۡرَكُوا۟ بِٱللَّهِ
We will cast into the hearts of those who have disbelieved the severest fear and terror as a result of their having committed shirk with Allāh. (Āli ʿImrān, 151)
And similarly, it is as Allāh, exalted be He in His majesty, says regarding the story of Al-Khalīl [Ibrāhīm], may Allāh increase him in protection against all faults and harms—
أَتُحَاجُّونِّي فِي اللَّهِ وَقَدْ هَدَانِ ۚ
Do you argue with me about [my worshipping] Allāh [alone] when He has guided me? (Al-Anʿām, 80)
—to His saying:
الَّذِينَ آمَنُوا وَلَمْ يَلْبِسُوا إِيمَانَهُمْ بِظُلْمٍ أُولَٰئِكَ لَهُمُ الْأَمْنُ وَهُمْ مُهْتَدُونَ
Those who have believed in Allāh and His Messenger [and acted upon what He has legislated] without mixing their īmān with shirk, those are the ones for whom there is serenity and security, and they are the ones who have been guided [to the true path]. (Al-Anʿām, 82)
¹treating other than Allāh as an equal of His in something that is only His (Tr.)
Majmūʿ Al-Fatāwá, vol. 28, p. 35.