Faith has become a funny word, full of misunderstanding and confusion. But the concept of saving faith is actually a very familiar one. James Montgomery Boice clarifies faith this way:
“Faith is the means, not the source, of justification. Faith is trust. It begins with knowledge, so it is not blind. It builds on facts, so it is not speculation. It stakes its life on the outcome, so it is not impractical. Faith is trusting Christ and proving his promises.” -Boice, Galatians (EBC), p. 449
Faith is therefore a simple practice with profound consequences.