Allah is the Creator and Controller, and associating others in worship with Him cancels out Good ...

Allah tells us that He is the Creator, Lord, Sovereign and Controller of all things; everything is subject to His dominion, power and guardianship.

لَّهُ مَقَالِيدُ السَّمَـوَتِ وَالاٌّرْضِ

Commentary

The word: مَقَالِيدُ (maqalid) in: لَّهُ مَقَالِيدُ السَّمَاوَاتِ وَالْأَرْ‌ضِ (To Him belong the keys to the heavens and the earth.- 39:63) is the plural form of: مِقلاد (miqlad) or: مِقلِید (miqlid) meaning a key. It has been said that this word has really been Arabicized from the Persian language. In Persian, a key is called کَلِید (kalid). When Arabicized, it became: اِقلِید (iqlid) with its plural being: مَقَالِيدُ (maqalid) (Ruh-ul-Ma’ ani). Having keys in one's hand denotes ownership, possession and the ability to dispense at will. Therefore, the sense of the verse is that the keys to whatever treasures lie hidden in the heavens and the earth are in the hands of Allah and He alone is the custodian and the dispenser in that it is He who gives whenever He wills to whomever He wills and as much as He wills - and would just not give to anyone He so wills.