Personality is like handwriting: It’s hard to change late in life. But it’s worth improving.
If someone can’t read your handwriting, you ought not say, “That’s just how I write.” No. You slow down and work hard at writing legibly.
If you’re being inhospitable, or unwelcoming, or unkind, or rude, or too agreeable (weak), or caustic (cranky), or joyless (not thankful), or inconsiderate (thoughtless), you ought not say, “That’s just my personality.”
Personality is not exempt from correction and sanctification. God is beginning a metamorphosis of your personality. At the resurrection it will be transformed.