Yes, thinking is important, but even in our thinking we can deceive ourselves. Similarly in our feeling, although perhaps less likely. It is our level of honesty which dictates how accurately we ascertain our thinking and feeling. But ultimately, what we are as defined by the effect of our thoughts, actions and speech on others, is our real scorecard.
I remember a significant experience in this regard - when I was forced to recognize that if I hurt someone's feeling with my humor, it was not their problem, but mine. To acknowledge my heartlessness under the guise of being light-hearted was painful, but salutory!! If I am serving others (with humor or otherwise) in a desire to do good, but not helping them, perhaps even weakening them, I am dishonest, plain and simple.
Honesty in self-examination is not always easy, but cannot be over-estimated: "Honesty is spiritual power. Dishonesty is human weakness which forfeits divine help." (S&H)
Do we wish to bless our fellow man, perhaps meet a need that has come to our door? If Jesus could say, "Of mine own self I can do nothing. The Father that dwelleth in me, He doeth the works," should we not be able to say the same? This is an honesty that lays aside self-righteousness, self-justification, self-love, and enables the reflection of divine Love, spiritual power!