The Importance of Allah's Mercy

In Surah al-Amaran there is a verse that applies to this particular phrase of the Prophet ﷺ which is a very important incident and a very beautiful phrase. It really demonstrates the reality of dawait Allah says, Lay sallakha minal ummbirishay. You have no matter or no share let's say in this issue. This is not yours to decide. Whether Allah punishes or forgives that's not yours but yes they have done vuum to you. SubhanAllah I mean what does it show us other than the reality of who is Allah ） and who is the abd?