Rabbi Abraham J. Twerski
Criticism is a sharp instrument. It can cut us as deeply as a surgeon's scalpel. A medical student must undergo many years of training before he or she can become a surgeon and make an incision which will lead to the improvement of someone's health. Even the most carefully calculated and well-performed surgical incision is a painful wound, and if the surgeon cannot apply himself to alleviating the patient's suffering and restoring his health, he has no right to make a cut.
Before we criticize someone, even if we have the finest intentions for that person's betterment, we should give serious thought to what we are doing. We must be aware that our remarks will inevitably cause emotional pain, and unless we are ready to assume responsibility for helping the person cope with the pain and assist him or her in making the changes we recommend, we should refrain from criticizing.