Eternal Security 13 - Matthew 28:20

Matthew 28:18-20 And Jesus came and spake unto them, saying, All authority is given unto me in heaven and in earth. 19  Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: 20  Teaching them to observe all things whatsoever I have commanded you: and, lo, I am with you alway, unto the end of the world. Amen.

Unless you think this doesn't apply to Christians for some reason that escapes me, this is a guarantee that even if we try to walk away, it will make no difference as our Good Shepherd will not desert us.