Q 41: What is the textual proof that when Faith is considered in detail, it refers to the six articles?
A--- It is the Prophet's (Peace be upon him) saying, when asked by Gabriel (Peace be upon him) about Faith: "That you affirm your faith in Allah, in His angels, His Books, His Messengers, the Day of Judgment, and you affirm your faith in the Divine Decree, be it good or evil". (Sahih Muslim)
Reference: 200 FAQ On Muslims Belief - Shiekh Hafiz Ibn Ahmed Al Hakami