The reading is from St. Paul's Letter to the Ephesians 4:7-13

BRETHREN, grace was given to each of us according to the measure of Christ's gift. Therefore it is said, "When he ascended on high he led a host of captives, and he gave gifts to men." (in saying, "He ascended," what does it mean but that he had also descended into the lower parts of the earth? He who descended is he who also ascended far above all the heavens, that he might fill all things.) And his gifts were that some should be apostles, some prophets, some evangelists, some pastors and teachers, to equip the saints for the work of ministry, for building up the body of Christ, until we all attain to the unity of the faith and of the knowledge of the Son of God, to mature manhood, to the measure of the stature of the fullness of Christ.