What is the significance of Exodus 32:33 ?

The Lord says “I will blot out of my book” all those who persist in rebellion against him.

If everything is eternally foreknown by God, one wonders why he would have recorded in his “book” the names of people who were to be blotted out eventually (cf. Rev. 3:5). Indeed, if God foreknew that certain individuals would have to be blotted from his book of life and would suffer eternal hell, one wonders why he created them in the first place.