In Matthew 10:28 Jesus said, 'And do not fear those who kill the body but cannot kill the soul. But rather fear Him who is able to destroy both soul and body in hell.' Jesus was telling us that we ought not fear him who can only take our life, but rather Him to can deprive us of eternal life. Clearly the contrast is between losing one's natural life versus losing out on eternal life. Following this verse Jesus goes on to point out how important we are to God. He then contrasts those who are confessed before the Father versus those who are denied. This entire passage is an admonition to be willing to die for the gospel if necessary, recognizing that just because someone can kill us does not mean we have lost out on the life that only Jesus can give.