not on your life

Adverb

idiomatic

(idiomatic) Absolutely not; under no circumstances.

Japanese Meaning

絶対にありえない / どんな場合でも認められない / 一切無理である

They asked if I'd ever steal from a friend, and not on your life would I do such a thing.

彼らは私に友人から物を盗むかどうか尋ねたが、私は絶対にそんなことはしない。

Sense（1）

(idiomatic) Absolutely not; under no circumstances.

Do you think I will ever go back after that? Not on your life!