“For in it the righteousness of God is revealed from faith to faith; as it is written, ‘The just shall live by faith.’” (Romans 1:17).
When selecting synonyms for the gospel, the New Testament penmen often made use of the word “faith” (Galatians 3:23, for example). Few inspired synonyms better encapsulate the divine and human aspects of the gospel.
The gospel is the once-for-all-time faith (Jude 3). It is the body of information revealed by God to inspired men who delivered it to the saints (1 Corinthians 15:1-3). Because it is the new covenant predicted by Jeremiah (Hebrews 8:8-12) with a high priest after the order of Melchizedek, not Aaron (Hebrews 5:1-11), it fulfilled (Matthew 5:18) and thus replaced the Law divinely given to Moses (Ephesians 2:14-16).
This body of information contains: 1) historical facts which undergird its impregnable, unshakable, solid foundation; 2) wondrous promises of spiritual victory to its adherents; 3) solemn warnings which ought to be universally heeded; and 4) divine commandments which must be obeyed.
The only acceptable human response to the faith is faith. Not some devilish, superficial acknowledgement of truth which even the demons have (James 2:16-20), but a deep conviction of immutable truth (Hebrews 11:6; John 20:30-31) which spawns deep trust and obedience like Abraham (Romans 4:16-22; James 2:21-24).
Human salvation results when the grace offered in the revealed faith is believed and its commands obeyed. Justification before God is not by works of the Law but by the faith of Jesus when we have believed in Christ (Galatians 2:16). Human faith comes by hearing the word of God, i.e., the faith (Romans 10:17).
The revealed gospel and its offer of righteousness is from faith to faith.