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speratus said:
"This do" refers to every aspect of the Supper.

Yes. But repeating "words of institution" is not a scriptural aspect of the Lord's Supper. It is only a man-made addition to it. Of course, there is nothing wrong with quoting the Scripture verses that show where the Supper was instituted when it is observed today, but this cannot be mandated because it is not mandated by the Word of God. And to think that repeating a certain set of words somehow invokes the presence of Christ in the observance of the sacrament is superstitious (I'm not sure if this is what you believe).



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speratus said:
There is one office in the NT for public preaching and administering the sacraments (the mysteries) that was instituted by Christ by whatever name that office is called. Acts 20:28.

"Take heed therefore unto yourselves, and to all the flock, over the which the Holy Ghost hath made you overseers, to feed the church of God, which he hath purchased with his own blood."

How does this verse support your view that only elders may administer baptism and the Lord's Supper?



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speratus said:
Christ calls qualified men to that office to preside over churches.

I agree. But I think it is an error to regard church officers as if they are a distinct class of holy men who mediate between the congregants and God, and somehow sanctify or at least legitimize the sacraments by their administration of them. I believe that their function is to instruct the other congregants in the meaning and proper observance of the sacraments and to oversee the observance of them in order to make sure that they are kept in accordance with scriptural teaching. The New Testament has done away with the human intermediaries of the Levitical system (who only temporarily symbolized the true Mediator), and I think it is inappropriate to make the administration of the sacraments the exclusive domain of church elders, as if they are Old Testament priests acting on behalf of the congregation. It seems to me that this creates an unbiblical clergymen/laymen distinction which is at variance with the New Testament doctrine of the priesthood of all believers.