John answered, "A man can receive nothing, unless it has been given him from heaven.

 It is John's grief that so few accept the message that Jesus brought; but when a man does accept it, he attests the fact that in his belief the word of God is true. In the ancient world, if a man wished to give his full approval to a document, such as a will or an agreement or a constitution, he affixed his seal to the foot of it. The seal was the sign that he agreed with this and regarded it as binding and true. So when a man accepts the message of Jesus, he affirms and attests that he believes what God says is true. 