Abdullah bin Buraydah narrates from his father (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever swears by trust (amanah) is not one of us (not on our way); and whoever deceives someone's wife or someone's slave is not one of us (that is, not on our way)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأيمان / 19836