Shri Krishna says in Mahabharata Karna Parv, Section 69 shlokas 33 and 34
"On an occasion of marriage, or of enjoying a woman, or when life is in danger, or when one's entire property is about to be taken away, or for the sake of a Brahmin, falsehood may be uttered. These five kinds of falsehood have been declared to be sinless. On these occasions falsehood would become truth and truth would become falsehood."
Check Hindi translation below from Gita Press Gorakhpur