24:7An-Noor

"When the Prophet commanded the two who were engaging in Li'an to utter the fifth oath, he commanded a man to place his hand over his mouth, and he said: "It will inevitably bring the punishment upon the liar.""

He who took an oath in order to entitle himself (to the possession) of a property, whereas he is a liar, would meet Allah in a state that He would be very much angry with him. Then the remaining part of the hadith was narrated as transmitted by A'mash but with the exception of these words: There was a dispute between me and another person in regard to a well. We referred this dispute to the Messenger of Allah (ﷺ). Upon this he remarked: Either (you should produce) two witnesses (to support your contention) or his oath (would be accepted as valid).

“Whoever swears a false oath in order to seize the wealth of a Muslim unlawfully, he will meet Allah when He is angry with him.”

He who took deliberately a false oath on a religion other than Islam would become that which he had professed. And he who killed himself with anything Allah would torment him with that in the Fire of Hell.

(who was one of the companions who gave the pledge of allegiance to the Prophet (ﷺ) underneath the tree (Al-Hudaibiya)) Allah's Messenger (ﷺ) said, "Whoever swears by a religion other than Islam (i.e. if somebody swears by saying that he is a non-Muslim e.g., a Jew or a Christian, etc.) in case he is telling a lie, he is really so if his oath is false, and a person is not bound to fulfill a vow about a thing which he does not possess. And if somebody commits suicide with anything in this world, he will be tortured with that very thing on the Day of Resurrection; And if somebody curses a believer, then his sin will be as if he murdered him; And whoever accuses a believer of Kufr (disbelief), then it is as if he killed him."