Dua when overcome by fear or anxiety

One should recite the following dua when overcome by fear or anxiety

حَسْبُنَا اللَّهُ وَنِعْمَ الوَكِيلُ عَلَى اللَّهِ تَوَكَّلْنَا

Allah Ta‘ala is sufficient for us, and He is the best guardian (who takes care) of our affairs. Upon Allah Ta‘ala alone we place our trust

عن أبي سعيد، قال: قال رسول الله صلى الله عليه وسلم: كيف أنعم وصاحب القرن قد التقم القرن واستمع الإذن متى يؤمر بالنفخ فينفخ فكأن ذلك ثقل على أصحاب النبي صلى الله عليه وسلم، فقال لهم: قولوا: حسبنا الله ونعم الوكيل على الله توكلنا (سنن الترمذي، الرقم: 2431)

Hazrat Abu Sa’eed Khudri (radhiyallahu ‘anhu) reports that Rasulullah (sallallahu ‘alaihi wasallam) said, “How can I enjoy life when the angel who has been deputed to blow the trumpet has already placed it in his mouth, with his ear turned in order to listen to the order to blow it so that he may blow it?” This statement weighed heavily on the Ṣaḥaabah (radhiyallahu ‘anhum), so Rasulullah (sallallahu ‘alaihi wasallam) said to them, “Say:

حَسْبُنَا اللَّهُ وَنِعْمَ الوَكِيلُ عَلَى اللَّهِ تَوَكَّلْنَا