Hadithcore
Riyad as-Salihin, 83

Anas (May Allah be pleased with him) reported:

Messenger of Allah (ﷺ) said, "Whoever says (upon leaving his house): 'Bismillah, tawakkaltu 'alallah, wa la hawla wa la quwwata illa billah <b>[I begin with the Name of Allah; I trust in Allah; there is no altering of conditions but by the Power of Allah]</b>,' it will be said to him: 'You are guided, defended and protected.' The devil will go far away from him". <b>[Abu Dawud, At-Tirmidhi and An- Nasa'i. At-Tirmidhi classified it as Hadith Hasan]</b>. Abu Dawud reported it with this addition: "One devil will say to another: 'How can you deal with a man who has been guided, defended and protected?".

العاشر‏:‏ عن أنس رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏"‏من قال-يعني إذا خرج من بيته-‏:‏ بسم الله توكلت على الله، ولا حول ولا قوة إلا بالله ، يقال له‏:‏ هديت وكفيت ووقيت، وتنحى عنه الشيطان‏"‏‏.‏ رواه أبو داود والترمذي، والنسائي وغيرهم‏.‏ وقال الترمذي‏:‏ حديث حسن، زاد أبو داود‏:‏ ‏"‏فيقول ‏:‏-يعني الشيطان-لشيطان آخر‏:‏ كيف لك برجل قد هدي وكفي ووقيّ ‏؟‏

References1 variant
In-Book Reference
Introduction, Hadith 83
Sharh · explanationclick to expand
<b>Guidance from the Hadiths:</b><br> 1) It instructs consistent reliance on Allah Almighty, seeking protection in Him, and supplicating him to bring benefit and fend off harm.<br> 2) The individual should fortify himself with the authentic Dhikr (remembrance of Allah) taught to us by the Messenger of Allah (may Allah’s peace and blessings be upon him) and aoivd Dhikr innovated by people, because blessings and goodness come about only through following what is reported from the Prophet (may Allah’s peace and blessings be upon him).<br> Note:<br> The individual cannot properly employ the reported Prophetic Dhikr unless he knows it, for knowledge precedes words and deeds. We must learn what our Lord sent us in the revelation so that we rejoice in it and dispense with it, and desert what we inherited of innovated Dhikr.<br> {Follow [O mankind] what has been sent down to you from your Lord, and do not follow any guardians besides Him. Little it is that you take heed!} [Al-‘Arāf: 3]