World Wide Study Bible
a Bible passage
16. He that believeth and is baptized—Baptism is here put for the external signature of the inner faith of the heart, just as "confessing with the mouth" is in Ro 10:10; and there also as here this outward manifestation, once mentioned as the proper fruit of faith, is not repeated in what follows (Ro 10:11).
shall be saved; but he that believeth not shall be damned—These awful issues of the reception or rejection of the Gospel, though often recorded in other connections, are given in this connection only by Mark.