The story of Florence Foster Jenkins is amusing and tragic. She was a wealthy New York socialite, who "performed" in many private concerts for her friends and celebrities. This tone-deaf "singer" was never told the truth about her awful voice and she kept on singing from 1920s to the 1940s. In 1944 she decided to perform in a public concert at Carnegie Hall.
Florence was deluded into thinking that she was indeed one of the greatest American sopranos. That night, in New York, proved to be fatal for Florence as she was exposed to the truth for the first time in her life. The public audience in that concert was brutal to Florence and all the newspaper music critics were even more vicious as they ruthlessly censured her performance.
Florence died a few days later.
Honesty is a wonderful trait to have and display, but only if it's properly accompanied by love. In fact, the Bible exhort us to always be: "...speaking the truth in love" (Ephesians 4:15). Love that is not informed and directed by the truth is only hypocrisy. Perhaps you know people like that. They always speak "flowers" to you, but throw daggers at you behind your back.
On the other hand, speaking the truth without love is cruelty of the highest degree. Just because something is true about someone, does not give us the right to say it, especially if we have not been asked to do so! This is not honesty, but brutality. This kind of misguided "honesty" has been responsible for the deaths of many marriages and relationships.
Yes the truth spoken without love can kill. We must be careful how we speak to each other because ill placed words (even if they are true) do hurt; sometimes more so than sticks and stones. We have probably forgotten many accidents and fights from our past, but some injuring words linger to this day.
The Word of God is true and it is,
"...living and powerful, and sharper than any two-edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart. And there is no creature hidden from His sight, but all things are naked and open to the eyes of Him to whom we must give account." (Hebrews 4:12, 13)
This Word of Truth is an instrument of salvation, consolation and hope for the believers, but the other "edge" of this sword brings condemnation and death to unbelievers. This is what happened to Pharaoh and to many others who hardened their hearts when they heard the truth.
The Word of God condemns sinners and it also kills sin. Paul says in Colossians 3:16:
"Let the word of Christ dwell in you richly" This is the only way to die to sin in and to live for Christ.