There is thus a clear complaint that too many of the Jewish Christians were attempting to teach what they did not clearly comprehend. This soon became an acute question, as one can see in I Cor.
Teachers are necessary, but incompetent and unworthy ones do much harm.
The reason is obvious. The pretence of knowledge adds to the teacher's responsibility and condemnation. James includes himself in this list of stumblers. The teacher uses his tongue constantly and so is in particular peril on this score. The wife is at liberty to test her husband by this rule of the tongue.