It is narrated from Sayyiduna Abu Musa Ash'ari (may Allah be pleased with him), he says: The Messenger of Allah (peace and blessings be upon him) addressed us one day and said: O people! Beware of this shirk, for it is more hidden than the crawling of an ant. A man said: O Messenger of Allah! Then how can we be safe from it, when it is more hidden than the crawling of an ant? The Prophet (peace and blessings be upon him) said: Say this supplication: "Allahumma inna na'udhu bika min an nushrika bika shay'an na'lamuhu wa nastaghfiruka lima la na'lamu." (O Allah! Indeed, we seek refuge in You from associating anything with You knowingly, and we seek Your forgiveness for what we do not know.)