Answered by Legionary of Christ Father Edward McNamara, professor of liturgy and dean of theology at the Regina Apostolorum university.
 Q: My question is about feasts of apostles celebrated as solemnities. Feasts normally have only two readings, for example, St. James on July 25. However, if St. James is the titular feast of the parish, it then becomes a solemnity. Whence does one get the third reading since the Common of Apostles only provides two? — J.G., Gilroy, California
 A: The principal criteria to be observed in this case are elucidated in the introduction to the lectionary. To wit:

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