Like most numbers in the Bible, "six" can have various meanings depending on context, but has a couple that are primary. When used in relation to time -- six days, six hours, six years, etc. -- six generally represents a state of labor, struggle and conflict, especially the conflict involved with spiritual growth. The six days of creation, for instance, represent the stages we go through in our lives, working toward the peaceful seventh day, in which our evil desires are removed from us and we can rest. In most other references, six represents all desires for good and all the true ideas that come from those desires for good -- or in the contrary sense, all evil and all the resulting false thinking.

'Waters' particularly signify the spiritual parts of a person, or the intellectual aspects of faith, and also their opposites.

'The waters above the firmament,' as in Genesis 1:7, signify the knowledges in the internal self, and 'the waters beneath the firmament' signify the knowledges of the external self.

'Waters,' as in Ezekiel 47:9, refer to the New Jerusalem, and they signify spiritual things from a celestial origin.

'Many waters,' as in Revelation 17:1, signify truths of the Word adulterated. 'Waters' or 'rivers' signify spiritual, rational, or scientific things pertaining to truth.

'Waters … that go softly,' as in Isaiah 8:6-7, signify spiritual things, and 'waters … strong and many,' signify falsities.

'Waters,' as in Psalms 104:3, signify divine truths.

'Waters' signify truths in the natural self, and in the opposite sense, falsities.

'The waters were dried up from off the earth,' as in Genesis 8:7, signifies the apparent dissipation of falsities.

(Odkazy: Apocalypse Explained 17; Apocalypse Revealed 50; Genesis 8)