Ecclesiastes 1:17
And I applied my heart to know wisdom, and to know madness and folly: I perceived that this also was a striving after wind.
Ecclesiastes 2:3
I searched in my heart how to cheer my flesh with wine, my heart yet guiding me with wisdom, and how to lay hold on folly, till I might see what it was good for the sons of men that they should do under heaven all the days of their life.
Ecclesiastes 1:13-14
And I applied my heart to seek and to search out by wisdom concerning all that is done under heaven: it is a sore travail that God hath given to the sons of men to be exercised therewith.
Ecclesiastes 2:10-12
And whatsoever mine eyes desired I kept not from them; I withheld not my heart from any joy; for my heart rejoiced because of all my labor; and this was my portion from all my labor.
Ecclesiastes 7:23-25
All this have I proved in wisdom: I said, I will be wise; but it was far from me.
1 Thessalonians 5:21
prove all things; hold fast that which is good;