From Sahih Bukhari (Hadith 423):
Narrated Sahl bin Sa`d:A man said, "O Allah's Messenger (ﷺ)! If a man finds another man with his wife, (committing adultery) should the husband kill him?" Later on I saw them (the man and his wife) doing Li`an in the mosque (taking oaths, one accusing, and the other denying adultery)
Reference: Bukhari 423