Mat 21:43 Therefore I tell you, The kingdom of God shall be taken from you, and given to a nation who shall bring out the fruits from it.

Alternative version: Therefore I tell you, God's rule shall be raised up from you, and given to the Gentiles who shall produce fruit from it.

In the context of discussing the capstone, the KJV translation of "taken from you" doesn't make great sense. However, if we understand the last verse correctly, it makes perfect sense. Christ is saying that he is the capstone of the wall that built upon the foundation of Israel. His work elevates God's reign up from the Jews and gives it to the Gentiles.

Notice that Christ uses the "kingdom of God" (basileia theos) here, not "the kingdom of heaven," the God's rule and not the universal rule.

"Shall be taken" is from aeirô , which means "to raise up," "elevate," "to bear," "to carry off," "to take and apply to any use," and "to cause to cease."

"Nation" is from ethnos, which means "a number of people living together," "caste," "tribe" or "nation," and implies a foriegn group. It is almost always translated as "Gentiles" in the New Testament.

"Bring forth" is from poieô, which has two general meanings of "make" and "do." In the sense of "make" it means "produce," "bring into existence," "bring about," and "cause." In the sense of "do," it means "to act" and "to be effective."

"Fruit" is karpos, which means both the fruit of trees and the fruit of your actions. In the later sense, it means "return" or "profit" as in a good tree produces good fruit.