What is the stance that should be taken when calamities recur: is it submission to destiny along with doubt in God's power, or trust in Him? And is the intention to fulfill the conditions of supplication sufficient to compensate for ignorance of them?

A prerequisite for supplication (Du'a) is that the Muslim must be certain of its acceptance and have good expectations of Allah, while striving to fulfill the conditions for acceptance and avoiding its impediments. Doubting Allah's power is disbelief (kufr), and the thought that supplication will not be answered contradicts faith in Allah's power and generosity. As for a Muslim's statement during calamities, "If calamities occur, I will accept the divine decree, perhaps they will end in good," this is not a doubt in Allah's power. Rather, it is an acknowledgement of the divine decree, good expectations of Allah, and indicates optimism and hope. The Muslim should continue to supplicate, as persistence in it is one of the reasons for its acceptance.