Charles Ellicott Commentary Ecclesiastes 11:5

"As thou knowest not what is the way of the wind, [nor] how the bones [do grow] in the womb of her that is with child; even so thou knowest not the work of God who doeth all." — Ecclesiastes 11:5 (ASV)

The wording of this passage leaves it ambiguous whether we have here two illustrations of man’s ignorance, or only one; whether we are to understand the verse as declaring that we know neither the way of the wind nor the growth of the embryo, or whether, retaining the translation “spirit,” we take the whole verse as relating to the latter subject. (Compare to John 3:6.) The word for “her that is with child” occurs in that sense here only in the Old Testament, and in later Hebrew.