God promised the land of Canaan to Abraham. When his wife, Sarah died, Abraham wanted to bury her in a cave on the land God had promised him. He believed God would return to Canaan land and resurrect his family, that is why he purchased the land he had already been promised.

Just as Abraham paid a price for resurrection, there is a price to be paid for sin. Some try to pay for salvation with their good works or with their tithes, but salvation is only obtained through grace by faith. God has provided the sacrifice for our salvation through Jesus Christ, His son.