Meaning of the word "the spirit is willing, but the flesh is weak" in English

What does "the spirit is willing, but the flesh is weak" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

the spirit is willing, but the flesh is weak

US /ðə ˈspɪrɪt ɪz ˈwɪlɪŋ bʌt ðə fleʃ ɪz wiːk/
UK /ðə ˈspɪrɪt ɪz ˈwɪlɪŋ bʌt ðə fleʃ ɪz wiːk/
"the spirit is willing, but the flesh is weak" picture

Idiom

used to say that someone wants to do something but is too tired or physically weak to do it

Example:
I'd love to go for a run with you, but the spirit is willing, but the flesh is weak.
He tried to stay awake to finish the book, but the spirit was willing, but the flesh was weak.