Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) says: False testimony has been made equal to associating partners with Allah Almighty. Then he recited this verse: "And shun false speech."
Al-Tabarani recorded it in al-Mu'jam al-Kabir, and its chain is hasan (good).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأحكام / 7039
Hadith Gradingمحدثین:إسنادہ حسن۔
Hadith Takhrij«اخرجه الطبراني فى المعجم الكبير (8569)»