It is narrated from Sayyiduna Ibn Amr, may Allah be pleased with him, that the Noble Prophet, peace and blessings be upon him, said: "The person whom Allah Almighty dislikes the most is the one who keeps moving his tongue like a cow chews cud."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 6543