St Luke tells us in Acts 8 that Philip had baptized the converts of Samaria but that they had not received the Holy Spirit until Peter and John came and prayed over them. What can this mean?
This was Philip the Deacon (not the Apostle), and the converts did receive the Holy Spirit and his Seven Gifts in Baptism, but they did not receive the full outpouring or perfection of the Gifts until the sacrament of Confirmation was given them by Peter and John.
The Sacrament of Confirmation is to Baptism what growth and maturing are to birth - Confirmation completes Baptism and brings to perfection the graces of Baptism. Confirmation is not absolutely necessary for salvation, but it is very difficult to make it to heaven without these graces.
Confirmation gives the Christian the sacramental strength to preach the Gospel and to endure persecution for the truth -- in this way, the Christian is united to the work of the Bishop, whose primary duties are to preach the Faith and to be willing to suffer martyrdom for the Gospel.
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