From the RCA website: rca.org/about/theology
Reformed Christians sometimes say we’re “Reformed and always reforming.” This means we never stop asking whether we’re being faithful to God’s vision and reforming the church to follow God’s will. We do this because we believe humans are broken. And we know how easy it is for our sinful nature to corrupt God’s church.
Scripture is the highest authority on our faith and its practice. Statements of belief called creeds and confessions also shape our faith and root us in Reformed theology. While people often associate the Reformed tradition with Calvinism, there’s more to our Reformed beliefs than the five points of Calvinism you may have heard about.