Allazeena amanoo watatmainnu quloobuhum bizikri Allahi ala bizikri Allahi tatmainnu alquloobu.
Those who believe, and whose hearts find satisfaction in the remembrance of Allah: for without doubt in the remembrance of Allah do hearts find satisfaction.
Surah Rad 28 Quran

Hazrath Abu Yahya Suhaib bin Sinan ^Rz. narrated: The Messenger of Allah ^PBUH said that-“How wonderful is the case of a believer; there is good for him in everything and this applies only to a believer. If prosperity attends him, he expresses gratitude to Allah and that is good for him; and if adversity befalls him, he endures it patiently and that is better for him”.-[ Sahih Muslim].

It is narrated that when (people) asked Hazrath Imam Mahdi ^PBUH to give them his foot wear or garments for good fortune as a memento and a blessing, the Imam Alaihissalam would give it to them and say:” Take it and wear it; do not keep it as a blessing (barkat) in the house. Even if you put on the skin of this servant (of Allah), you will never be saved from the Hell, unless you do what this servant of Allah asks you to do.”

Hazrat Ali -ul Murtuza ^Rz said that:He that has no courage has no religion.