The only difference in religion is concerning the way a sinner is saved. "What must I do to be saved" is the question asked. And since it is a question we ask, it must be answered. How we answer this determines the place of our soul in eternity. When this is answered, we will respond with one of only two ways of Salvation, works or Grace. It cannot be of both for they cannot stand together. They contradict one another. Either we must come before God in our own righteousness, or we will stand before Him in the righteousness of Christ.
"Christ Jesus came into the world to save sinners." The way of God for saving sinners comes from infinite wisdom. Some receive it and are saved, others reject it and are damned. To one this is the wisdom and power of God, and to another this is foolishness. There is no middle ground. Either Christ saves or He does not. We either come to God in Christ or we do not. Salvation is either all of Grace or all of works. So many are blinded by Satan, their minds are so prejudiced against the Gospel, their hearts are so in love with the things of this world, that the light of the Gospel cannot shine in them. Unbelief in God's way of Salvation etemally ruins the souls of men.
All Scripture declares that God's way of saving sinners is by substitution, atonement, satisfaction, and imputation. The first promise made by God declared this. All the sacrifices of the Law pointed to this. "By the deeds of the Law there shall no flesh be justified in His sight" "If thou, LORD, shouldest mark iniquities, O Lord, who shall stand?"
The way of Salvation is by the substitution of a Mediator, who both bore the penalty of the law and fulfilled that righteousness which was required. "For what the law could not do, in that it was weak through the flesh, God sending His own Son in the likeness of sinful flesh, and for sin, condemned sin in the flesh; that the righteousness of the law might be fulfilled in us," "He made Him to be sin for us, who knew no sin; that we might be made the righteousness of God in Him"
God's way of saving is through the Person, mediation, blood, righteousness, and intercession of the Lord Jesus Christ alone.