How Did Jesus Christ Create Grace and Truth?

"For the law was given through Moses; 

grace and truth came to be through Jesus Christ." 

-John 1:17 (literal translation from the NASB marginal note)

Didn't grace and truth exist before the incarnation? Could it be that they existed in the character of God and that the death and resurrection of Christ was the place where God made them a reality in the moral world? God passed over all sin before Christ so that the cross would be the place of the revelation of His righteousness. -Romans 3:24-26

If the cross is the place where grace and truth were established, then wouldn't it be good for you to always keep that at the front of your mind—goodness as all or nothing and provided by Christ—when others sin against you, hate you, reject you, and cast you out as evil? The cross is the place of celebration. Let's turn up the music.