Trying to live up to the high ideals that I set for myself years ago is not easy.  I am like all of us....The spirit is willing, but the flesh is weak," as Matthew reminded us (Matthew 26:41). 
I can't speak for others; but for myself, when I allow the desires of the flesh (and I am not necessarily speaking of sexual desirses)to control me, those are my worst moments.  
Those are the moments when I say or do things that I later regret.  On the other hand, when I listen to my spirit, I hold my tongue and I think before I act.
We all have an Achilles' Heel. My quick temper is mine.

According to legend, Achilles, the great Greek hero who fought in the Trojan War, was immortal except for his heel. Thetis, Achilles mother, was informed when Achilles was a baby, that in one of his battles he would die from an arrow.

Thetis, being only a mother, did not want her son to die. So Thetis took Achilles to the River Styx (which surrounded the underworld) and dipped his body into the magical river; holding him by the heel. But Achilles's heel would be unprotected because the water did not touch it.

. As he matured, Achilles grew to be a man of war. He surrvived many great battles. But one day an arrow was shot to his heel, killing him instantly. Therefore destiny is destiny and shouldn't be over-looked.

The moral lesson here, of course, is that we cannot change life's paths...that things will play out exactly as they are fated.

But the term has come to have broader implications. It is used commonly now to denote a person's most vulnerable mental trait...one that may lead to that person's ultimate downfall as well.

I constantly try to guard against saying something that I may later regret.  Most of the time I win, but sometimes I lose.
I recently said some things that I wish I had not said.  I could give excuses as to why I said them; but I don't believe in rationalizing my bad behavior with excuses.
Therefore, I will just add that there is no excuse for what I said; and I am truly sorry.

P.S. It was true but I still shouldn't have said it at this particular time.