Such is our folly, that when we are left at liberty, all we are able to do
is go astray. And then when once we have turned aside from the right path, there is no end to our wanderings, until we get buried under a multitude of superstition. (Necessity of Reforming the Church, 17)
Some seem all too blind to slippery slopes. They think little of the consequences of so slight an adjustment in policy. They think that just "bumping the boat" will have little affect on the direction. What's the harm in a little fun while we worship? What's the harm in a Saturday night rather than a Sunday morning? What's the harm in a little music?
I suppose the folks in Matthew 6 felt that way. What's the harm in a little paint on my face? What's the harm in praying before others? What's the harm in letting others know I give?
I can just imagine someone saying some of these things:
"If we can play the instrument, why can't we serve roast lamb on
the Lord's Table? If we can play the instrument, let us also burn incense, offer grain offerings, and dance before the Lord. Why not just become Jews? Jesus was a Jew. The apostles were Jews. What difference does it make whether we bring in God's approved worship under the Old Covenant? Perhaps we should build an altar like Ahaz and put it up front for our offerings?"
Open the door to more and more digression and departure from the simple teaching of the New Testament and we will come to be a church after our own imagination. How easily people justify their departures... How easily they justify their desires...