"yahweh created a covenant with abraham. this covenant held that abraham and his descendants would receive the land of canaan as a sign of the relationship between yahweh and the people of abraham." this statement is most important when describing the foundation of what religion?

 Judaism

Details:

The covenant that YAHWEH made with Abraham was a unilateral (one-sided) promise.  Apart from anything Abraham did, God was promising that he was going to bring about a great nation from Abraham's offspring, and that the nation descended from him would possess the land of Canaan.  The descendants of Abraham are the Jewish people, and Canaan became known as their land, Israel.  (Israel was a name God gave to Abraham's grandson, Jacob, that then became the name of his descendant people.)  

God also included the promise of a Messiah in the covenant with Abraham, saying, "Through your offspring all nations on earth will be blessed" (Genesis 22:18).

See Genesis chapter 17 and also Genesis 22:15-18 for the Bible's account of these covenant promises.