Shaykh ‘Abd ur-Razzaaq al-Badr (hafidhahullaah) comments:
“And indeed as a result of having faith in the name of Allaah ‘Al-Mujeeb,’ the slave’s certainty in Allaah strengthens, and his turning to Him and hoping for what is with Him increases, and the disease of despairing from His Mercy departs from him. And how can the Muslim not trust in his Lord, the Most Generous, while in His Hand, subhaanah, is the kingdom of everything. So whatever He wills, will be, at the time that He wills, in the way that He wills, with no addition nor omission, no precedence nor delay; and His decree, subhaanah, is carried out in the heavens, and the earth and what is upon it and what is under it, and in the seas and the air, and in all the parts and atoms of the world. To Him belongs the creation and the command, to Him belongs the kingdom and the praise, to Him belongs the dunyaa and the aakhira.”
“And His Name, ta’aala, ‘Al-Mujeeb’ shows that He, subhaanah, hears the du’aa of those who supplicate, and answers the request of those who ask, and does not disappoint a believer who has called upon Him, and He, subhaanah, loves that the slaves ask Him for all their needs of the deen and dunyaa, such as food, drink, clothing and shelter, just as they ask Him for guidance, forgiveness, success, assistance to obey (Him), and the like; and He promised them the response to all of that, no matter how great the request is, how much it is, and how diverse the wishes are; and in this, there is evidence of the absolute power of Allaah, subhaanah, and that His treasures will are not depleted nor diminished by (His) giving, even if He granted the first and the last of the jinn and mankind all that they asked Him, as is in the hadeeth qudsee.
And it has been mentioned in the Prophetic Sunnah that Allaah, tabaarak wa ta’aala, answers those who supplicate and gives those who ask, and that He, jalla wa ‘alaa, is Shy and Generous, too Generous to turn away the one who calls upon Him or disappoint the one who confides in Him with humility or prevent the one who asks Him.”
Source: Fiqh ul-Asmaa il-Husnaa; Chapter 63, p. 250, 251,253