Manyyasha’ = In accordance with His Laws = Per His due measure. Erroneously translated as ‘Whom He wills’. (Ref: QXP)
Let's remember that
I- God does not intervene in our life.
II- Something may happen beyond our control.
III- When we fail to understand a certain event, we call it chance.
18:23 (This is the news of the Unseen, like the next day is unseen for you.) Never say about a thing, “Certainly, I will do it tomorrow.” [Something may happen beyond your control]
18:24 Add to your statement, “If my promise is not contrary to the Divine Laws” - And remember your Lord if you forget your promise, and say, "I hope my Lord will guide me even closer to the right course.”