I fail to see what posture, holding hands, or any other physical motion has to do with prayer. What difference does it make? And by what authority does the clergy dictate to the people their posture in prayer? Is there somewhere in the Bible that we are told to bow our heads? Or fold our hands? Or kneel? Or stand? Or lie face down on the floor?
The same authority by which the Church instructed believers to "abstain from things sacrificed to idols, and from blood, and from things strangled" (Acts 15:29).