How can trust in Allah when supplicating be reconciled with belief in divine decree and destiny?

One's destiny is by the decree of Allah the Almighty. A Muslim should entrust his affairs to Allah and be content with what He decrees and ordains, while maintaining good thoughts about Him, Glorified be He. He should know that Allah's choice and management for him are better than his own choice and management for himself, and that He is more merciful to him than his own mother. Therefore, one must combine good thoughts about Allah with contentment with His decree, submission to His judgment, and trust in what comes from Him, along with supplicating with certainty that Allah's choice is good and His management is beneficial.