Mukhtasar Bukhari (Abridged) 2147 — One who breaks an oath by mistake

Narrated by Abu Huraira (may Allah be pleased with him) from the Prophet (peace and blessings of Allah be upon him): He (peace be upon him) said, "Allah the Exalted has pardoned my Ummah for the whispers and thoughts of the heart, as long as they do not act upon them or speak about them."