Amir al-Sha'bi عامر الشعبي · The Chapters on Rulings

the Messenger of Allah (ﷺ) passed judgment on the basis of an oath (from the claimant) along with a (single) witness.

the Prophet(ﷺ) prayed the Morning prayer, and when he had finished, he stood up and said: “Bearing false witness is equivalent to associating others with Allah,” three times. Then he recited this Verse: “And shun lying speech (false statements), Hunafa' Lillah (i.e., worshiping none but Allah), not associating partners (in worship) to Him.”