Who adminsters baptism?

Probably one of the biggest questions to ask about baptism is:

• Is baptism primarily an act of, or upon, the person baptised?

Interesting to hear what a Baptist scholar may say about that based on the evidence...

Some Jewish groups practised 'proselyte baptism', i.e. proselytes were baptized in the process of converting to Judaism. In the monastic community at Qumram, members invoked passages such as Ezekiel 36:25 to justify their daily baptism... But in both instances baptism was self-administered. Candidates baptized themselves... One of the things that characterized the baptism of John the Baptist is that he himself administered it. It may even be that the authority implicit in such an innovative step triggered the assumption in the minds of at least some Pharisees that John's baptism was an end-time rite administered by an end-time figure with great authority.

(italics original, p.145, DA Carson, The Gospel According to John)

Carson notices that if baptism is primarily something done by one with authority to the person baptised there is a secondary question of who has such authority. John Calvin suggests an answer in commenting on John 4:2 where the Evangelist says that Jesus baptised, and yet also clarifies that it was only his disciples who did the action:

He gives the designation of Christ’s Baptism to that which he conferred by the hands of other, in order to inform us that Baptism ought not to be estimated by the person of the minister, but that its power depends entirely on its Author, in whose name, and by whose authority, it is conferred. Hence we derive a remarkable consolation, when we know that our baptism has no less efficacy to wash and renew us, than if it had been given by the hand of the Son of God.

PS I am sorry. I know that Christmas Eve is probably not the time to riding one of my hobby-horses.