The grace of faith by which the elect are enabled to believe, so that their souls are saved, is the work of the Spirit of Christ in their hearts, and is ordinarily brought into being by the ministry of the word. It is also increased and strengthened by the work of the Spirit through the ministry of the word, and also by the administration of baptism and the Lord’s Supper, prayer, and other means appointed by God.
By this faith a Christian believes to be true whatever is revealed in the word for the authority of God himself, and also apprehends an excellency in the word which is higher than in all other writings and everything else in the world as it bears forth the glory of God in his attributes, the excellency of Christ in his nature and offices, and the power and fullness of the Holy Spirit in his workings and operations: and so is enabled to cast his soul upon the truth thus believed; and to see and respond to the different kinds of teaching which different passages of Scripture contain. Saving faith equips him to obey the commands, hear the threatenings with fear and respect, and to embrace the promises of God for this life and the life to come. But the first and most important acts of saving faith are those directly to do with Christ, when the soul accepts, receives, and rests upon him alone for justification, sanctification and eternal life, by virtue of the covenant of grace.
Although this faith may be different in degrees, and may be weak or strong, nevertheless is even at its very weakest in an entirely different class and has a different nature (like other aspects of saving grace) from the kind of faith and common grace which is possessed by temporary believers. Therefore, though it may be frequently assailed and weakened, it gets the victory, growing up in many to the attainment of a full assurance through Christ, who is both the author and finisher of our faith.