Now we command you, brothers, in the name of our Lord Jesus Christ, that you withdraw yourselves from every brother who walks in rebellion, and not after the tradition which they received from us.
The current widespread offerings of prayers without the "name on lip" mention of the Holy Saviour, in whose name alone any man has right of access to the Father, is a violation of the principle manifest in this verse.  When Paul prayed or commanded "in the name of the Lord Jesus" he never forgot to make audible mention of it.