Why is the Torah compared to water?
Song of Songs Midrash Rabbah 1, 19
The Torah has been compared to water; just as we find water all over the earth's surface, so do we find the Torah.
Water will never cease from this globe, neither will God's laws cease.
Water comes from the heavens, and the Torah came from heaven.
Water cleanses impurities, and God's laws do the same.
Water coming down by drops can form a river, and so the Torah: if a man acquires Torah bit by bit he may eventually become a great scholar. A man of distinction will not think it beneath his dignity to ask for water from the meanest individual, neither is any one too great to despise instruction from the most insignificant person, and ask him: teach me one chapter, one saying, one verse, even just one letter.
One may drown in water if one cannot swim; so, unless one possesses a thorough knowledge of the Torah and all its meanings, one may be drowned in it.”