Let's skip all this confusion about whether the "Gospel is not based on passages...". If you have your own definitions tell me what they are, but I suggest we use these:
gospel
Pronunciation: (gos'pul), [key]
n.
1. the teachings of Jesus and the apostles; the Christian revelation.
passage
Pronunciation: (pas'ij), [key]
n., v., -saged, -saging.
n.
1. a portion or section of a written work; a paragraph, verse, etc.: a passage of Scripture.
Scripture
Pronunciation: (skrip'chur), [key]
n.
1. Often, Scriptures. Also called Holy Scripture, Holy Scriptures. the sacred writings of the Old or New Testaments or both together.
Gospel was given to the Church of Christ at the time of His earthly sojourn, death and resurrection and through sending of the Holy Spirit during the Pentecost.
The holy books and passages were written AFTER the Gospel was given. So the Books of New Testament are based on the Gospel and Gospel is not based on them. The pillar and ground of Truth is the Church (1Tm:3:15). The Church wrote, selected and canonized the Scriptures under inspiration of Holy Spirit, first were the Apostles and then there were the books of New Testament, first were the patriarchs and prophets and then there were the books of Old Testament.