Untill one come into the knowledge, that they themselves wit hall there learning, know nothing, than they remain unteachable, A glass full needs to be emptied of what it contains so that it can be filled with what it need. Jesus used the "empty" vessels prepared for the sacrifice to be filled with water so that is could be turned into wine.
1Co_1:28 And base things of the world, and things which are despised, hath God chosen, yea, and things which are not, to bring to nought things that are:
Luk_10:21 In that hour Jesus rejoiced in spirit, and said, I thank thee, O Father, Lord of heaven and earth, that thou hast hid these things from the wise and prudent, and hast revealed them unto babes: even so, Father; for so it seemed good in thy sight.
Amen