'Understand' in the Bible

Who is the wise man, that may understand this? and who is he to whom the mouth of Jehovah hath spoken, that he may declare it? wherefore is the land perished and burned up like a wilderness, so that none passeth through?

The anger of Jehovah shall not return, until he have executed, and till he have performed the intents of his heart: in the latter days ye shall understand it perfectly.

The fierce anger of Jehovah shall not return, until he have executed, and till he have performed the intents of his heart: in the latter days ye shall understand it.