Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "When a man, while speaking, looks this way and that, then what he says is a trust." [Hasan]
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 21161