2 Nephi 27:8

Wherefore, because of the things which are sealed up, the things which are sealed, shall not be delivered in the day of the wickedness and abominations of the people. Wherefore the book shall be kept from them.

Because of the things that are sealed up, those sealed things will not be given in the day when people are wicked. So the book will be kept from them.

Because of what’s sealed up inside, these sealed portions won’t be given to the people during their time of wickedness and corruption. The book will be kept from them.