Baptism in the Holy Spirit is not a new sacrament but rather an awakening of the graces of Baptism and Confirmation. Most of us were baptized as babies. We received the Holy Spirit but we need to consciously respond with our personal assent to Him, giving the Lord full authority over our lives. The principal fruit of the baptism in the Holy Spirit is to come into a deep relationship with Jesus in the power of the Holy Spirit and therefore a desire to respond to Him giving ourselves completely to the Father.

Pope Benedict XVI:
"The Acts of the Apostles present Pentecost as the fulfillment of this promise and hence as the culmination of Jesus' entire mission. After his Resurrection, he himself ordered the disciples to stay in Jerusalem, because, he said, "before many days you shall be baptized with the Holy Spirit" (Acts 1: 5); and he added: "You shall receive power when the Holy Spirit has come upon you; and you shall be my witnesses in Jerusalem and in all Judea and Samaria and to the end of the earth" (Acts 1: 8). Thus Pentecost is in a special way the Baptism of the Church which carries out her universal mission starting from the roads of Jerusalem with the miraculous preaching in humanity's different tongues. In this Baptism of the Holy Spirit the personal and community dimension, the "I" of the disciple and the "we" of the Church, are inseparable. The Holy Spirit consecrates the person and at the same time makes him or her a living member of the Mystical Body of Christ, sharing in the mission of witnessing to his love. And this takes place through the Sacraments of Christian initiation:  Baptism and Confirmation. In my Message for the next World Youth Day 2008, I have proposed to the young people that they rediscover the Holy Spirit's presence in their lives and thus the importance of these Sacraments. Today I would like to extend the invitation to all:  let us rediscover, dear brothers and sisters, the beauty of being baptized in the Holy Spirit; let us recover awareness of our Baptism and our Confirmation, ever timely sources of grace. ( Regina Coeli, Pentecost 2008)

Benedict XVI
Lenten Reflection, 2011
...this Sacrament (baptism) realizes the great mystery in which man dies to sin, is made a sharer in the new life of the Risen Christ and receives the same Spirit of God who raised Jesus from the dead (cf. Rm 8: 11). This free gift must always be rekindled in each one of us, and Lent offers us a path like that of the catechumenate, which, for the Christians of the early Church, just as for catechumens today, is an irreplaceable school of faith and Christian life. Truly, they live their Baptism as an act that shapes their entire existence.