"But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him." (Hebrews 11:6)
Gospel knowledge is essential to saving faith. And the matter of paramount importance in the knowledge of the gospel is the redemptive work of Christ. Because he is the God-man, we are assured that he is an able Redeemer, a willing Redeemer (Isa. 53:5-7), and an effectual Redeemer (Isa. 53:10-11). Until a person knows these things, he simply cannot be saved, for he cannot have faith. Gospel knowledge is essential to saving faith. Unless a person knows these things, he cannot have faith, he cannot please God, he cannot be saved; but merely knowing these things is not faith. Knowledge is necessary. But knowledge alone is not faith.
“Of all the poison which at this day is diffused in the minds of men, corrupting them from the mystery of the gospel, there is no part that is more pernicious than this one perverse imagination, that to ‘believe in Christ’ is nothing at all but to ‘believe the doctrine of the gospel!’ which yet we grant is included therein.” – (John Owen)
Along with that knowledge, our hearts must give assent that these things are true. Many people know the truth. They have heard it for years. They have been catechized and trained in gospel truth from their infancy. But saving faith involves a willing, voluntary, deliberate, considered assent to the truth of God. Faith simply embraces the Revelation of God as the Revelation of God.
Hearing the gospel, sinners are being confronted with the truth of God. The Word of God is open on their laps. The truth stares them in the face. God speaks directly to their hearts. As that happens, each one makes a decision, willfully and deliberately. Each one either embraces the testimony of God as the Truth, or he rejects it and declares that God is a liar (1 John 5:10).
Have you now embraced this gospel of God’s free grace as the truth? If you have, you are not far from the kingdom of God. Still, something else is necessary. Faith knows the gospel and gives assent to the gospel of the truth. But there is more
Saving faith trusts the Lord Jesus Christ. A person acts upon what he believes, and the act of faith is trusting Christ. The woman with an issue of blood did not simply say, “I believe Christ can heal me”. She touched him. The publican did not merely believe there is propitiation at the Mercy Seat; he sued for mercy upon the grounds of propitiation made. The leper did not simply think within himself, “Christ can make me whole if he will.” He came to the Master.
Faith is more than knowledge and assent. Faith is acting upon that revealed knowledge of which we are convinced. Faith is trusting the Son of God!
“He that believeth on the Lord Jesus Christ shall be saved, be his sins never so many; but he that believeth not in the Lord Jesus must be damned, be his sins never so few” – (Thomas Brooks).
Why is faith in Christ necessary? Why is it necessary for sinners to trust the Lord Jesus Christ alone in order to be saved? It is necessary, because no sinner can be accepted of God upon any other ground. Hebrews 11 records the names of 17 men and women, whose histories are well known, who pleased God. How did they do it? By faith alone! Many others, mentioned in the Bible, have perished under the wrath and curse of God, though they did some good, commendable things.
Repentance will not save you. Esau, King Saul, and Judas all repented, but still went to hell. The confession of sin will not save you. Both Saul and Ahab confessed their sins, but perished still. Self-denial and sacrifice will not save you. Ananias and Sapphira made great, costly sacrifice; but their very sacrifice was a lie, for which they fell dead in the house of God. Only faith pleases God, because only faith gives all praise, honor, and glory to the Son of God.
Faith is necessary, because without faith there is no vital union with Christ. Faith is necessary, because God plainly declares that works have nothing to do with salvation (Eph. 2:8-9). Faith is necessary, because salvation is by grace alone (Rom. 4:16; Gal. 5:2-4; 2 Tim. 1:9). Faith brings nothing! Faith promises nothing! Faith does nothing!
Because faith looks to Christ alone for everything, the cry of faith is, “By the grace of God I am what I am. – Not unto us, O Lord, not unto us, but unto thy name give glory, for thy mercy and for thy truth’s sake!” Faith understands that all who are in Christ are in him by God’s work alone. Faith understands and rejoices in the fact that Christ is made of God unto us Wisdom and Righteousness, Sanctification and Redemption. Faith hears God say, “He that glorieth, let him glory in the Lord.” And faith says—“AMEN!”