James 3:8

but the tongue can no man tame; it is a restless evil, it is full of deadly poison.

Carson's observation that "Fortunately James did not say that God cannot control the tongue (or tame it),"[26] while true enough, fails to touch the problem, namely, that the tongue is indeed out of control because of man's failure to exercise the dominion over it that God commanded. It was true in James' day, as it is in this, that:

It is a restless evil ... It is like a caged beast, even under the best of circumstances, ever seeking an opportunity to break forth and set the whole world on fire. James does not mean here that a Christian cannot tame his tongue. "If he could not, he would hardly be responsible for its vagaries; but in James 3:10, he said, `My brethren, these things ought not to be so.'"[27]

It is full of deadly poison ... This is similar to "full of adultery" (2 Peter 2:14), and "full of envy" (Romans 1:29). Paul also made use of the same metaphor: "The venom of asps is under their lips" (Romans 3:13).

[26] T. Carson, op. cit., p. 577.

[27] E. G. Punchard, op. cit., p. 370.