St. Augustine, in Sermon 4 on the Epiphany (De Temp. 42).  From Sunday Sermons of the Great Fathers, vol. 1, p. 198.

These Wise Men, what were they but the first fruits of the Gentiles?  The shepherds were Israelites, the Magi Gentiles.  The former from close by, the latter from far away;  both hasten to the Corner Stone.  (Again, from Serm. 2.) Jesus is made manifest neither to the learned nor to the just.  For ignorance dominated the rusticity of the shepherds, impiety the practices of the Magi.  But that Corner Stone joins them both to Himself, Who came to select the foolish that He might confound the wise, and to call not the just but the sinners to repentance; so that no great one might take pride in himself, and no lowly one despair.