Jack Dean Kingsbury, "The Figure of Peter in Matthew's Gospel as a Theological Problem." JBL 98 (March 1979): 67-83.

The church was built on Peter the "rock," but Peter was no more than first among equals in relation to the other disciples. Matthew brings the salvation-historical primacy of Peter to bear on the gospel story by enlarging on his traditional role as spokesman for the disciples and by making him typical of the disciples and of other Christians.