What is the intended by "and unto Allah all matters are returned"? Does this imply that they were outside His grasp at some point?

Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. The verse is meant to inform the people that Allah is the one who rewards and punishes based on deeds. [Al-Zajjāj]
2. Because some people worshipped others besides Him and attributed His actions to others, when the veil is lifted on the Day of Judgment, they will give back to Allah what they falsely attributed to others.
3. The Arabs use similar expressions, such as "Something harmful has returned to me from so-and-so" meaning that harm has come to him from that person, even if it had not occurred previously. (That is, all affairs will ultimately end up with Allah, not that they were in someone else's control before.)
4. Everything was with Allah before creation, then He brought people into existence and gave them some control; after their death, all matters return to Him.