So many today believe that simple mental ascent of belief in God is sufficient to be called a saving faith, and yet the Bible teaches that even the demons had reached this level (James 2:19) and assuredly they were still erring.  So what does the New Testament describe as a saving faith (I Peter 1:9)?
    Let us notice that "faith is the substance (foundation-DFC) of things hoped for, the evidence (assurance-A.S.V.) of things not seen."  (Hebrews 11:1).  If faith is the substance of something else then it cannot be an end in itself, just as a house is not completed when all that exists is a foundation.  Having said this, Paul (likely the writer of Hebrews) went on to write in verse 6 that "without faith it is impossible to please" God.  Paul then finishes the thought by naming 15 examples of saving faith.  What made the faith of these 15 so special?
    The faith of those listed in Hebrews 11 was special and saving because it was a living, active, and working faith.  The faith of each of those examples led to action, and the hope was realized.  James 2:20 (in context of the devils or demons believing) affirmed "that faith without works is dead (barren-A.S.V.)"  Three other times in that same chapter the points is repeated, a saving faith is one which leads to action.  Look again at Hebrews 11.  When was Noah saved?  When his faith led him to build the ark and get in it.  Consider this, everyone of the examples of faith in Hebrews 11 is written in this form:  "By faith" (so-and-so) (did this-or-that), "and" (the result of faith conjoined with works is seen).
    Finally consider an example of faith in the New Testament.  The date is Pentecost, the occasion is the first Gospel sermon and the beginning of the church, or kingdom.  The speakers are the inspired apostles, and the audience is made of Jews from around the world, some of whom had just crucified our Lord.  On this day the apostles preached a sermon about the prophecies concerning the resurrection of Christ and the birth of the church.  They conclude by saying that the men of Israel were the ones who had crucified the Savior.  How did the men respond?  3000 responded by believing what had been preached and then taking action on that belief (in verse 41 the Bible teaches that they were baptized which according to verse 38 washed their sins away).  Were this verse found in Hebrews 11 I have every confidence it would read like this:  "By faith 3000 men of Israel were baptized and their sins were forgiven."  That is a saving faith.