Is confirmation as a sacrament mentioned in the bible?
The sacrament of confirmation is the reception of the Holy Spirit through the laying on of hands. This is separate from baptism as can be seen in the New Testament.
Now when the apostles in Jerusalem heard that Samaria had accepted the word of God, they sent them Peter and John, who went down and prayed for them, that they might receive the holy Spirit, for it had not yet fallen upon any of them; they had only been baptized in the name of the Lord Jesus.
Then they laid hands on them and they received the holy Spirit.
– Acts 8:14-17