The Gospel of Christ is the power of God to salvation for everyone who believes, for the Jew first and also for the Gentile (Romans 1:8-17). Even in the Old Testament, the Gentiles were beneficiaries of God's saving power. Though unimpressed at first with the Word of God, a Syrian commander is persuaded to receive that Word, and in the water he is cleansed and brought to faith in the God of Israel (2 Kings 5:1-15a). Evil is overcome by good (Romans 12:16-21). So also in the New Testament, a Roman centurion demonstrates great and humble faith in the Lord (Matthew 8:1-13). All he needs is the Word of Christ, for he trusts that Jesus' Word of healing has authority to accomplish what it says. And indeed it does. The centurion's faith is praised by our Lord above that of any Israelite. For the last shall be first, and the first last. Apart from faith in Christ, there is no salvation--not even for a Jew--but only weeping and gnashing of teeth.
