The role of Christ in Christianity, and the form we have come to accept Christianity as today, can namely be attributed to the contributions of Paul to reframing Hebrew thought, with Greek influence, to come up with a new position for Christ to fill. The Hebrew Law was too rigid, keeping Christianity isolated to only persons who also accepted the tenants supported by Judaism. To resolve this, Paul displaces the Law as the center, or core, of the religion and rather have the position of Christ become center, negating the primary barriers of Jewish practice to keeping people from Christianity. With God becoming a human figure, which wasn’t a new concept, it allows the inclusion of all humanity into Christian acceptance and the potential for salvation.
The Gospels, then, when written, coincide with this new theological approach to Jesus and Hebrew thought.