(If you are suffering [hardships] then surely, they [too] are suffering [hardships] as you are suffering, but you have a hope from Allah [for the reward, i.e. Paradise] that for which they hope not...)
(Qur’an 4: l04)
For the reason mentioned in this verse, the true believer has a high level of tolerance when he is afflicted with calamity. Patience, steadfastness, serenity, and a sincere desire to fulfill one’s duty as a slave of Allah --- these are qualities that you can find in a true believer. Ma’qil ibn Yasaar (may Allah be pleased with him) related that the Prophet (bpuh) said:
"Your Lord, Most Blessed and Most High, says: O’ son of Adam, Dedicate your time to my worship and I will fill your heart with wealth and your hands with sustenance. O’ son of Adam, don’t distance yourself from Me or I will fill your heart with poverty and your hands with problems that will preoccupy you."