The answer
The psalms were written by individuals, mainly David the prophet, but also others, like Solomon, Asaph, Moses. Each one is expressing a personal thought, feeling, prayer, remorse, pain, hope, joy, vision, thankfulness, etc., whereas the Orthodox Creed was written for the people of the true Orthodox faith to confirm their faith with boldness and conviction on this doctrine. The Creed was also written to defend the Church against heresies. We are the Church, not just individuals. We are collectively the body of Christ.Answered by His Eminence Metropolitan Youssef (opens in a new tab)