Albert Barnes Commentary James 3:5

"So the tongue also is a little member, and boasteth great things. Behold, how much wood is kindled by how small a fire!" — James 3:5 (ASV)

Even so, the tongue is a little member. Little compared with the body—as the bit or the rudder is, compared with the horse or the ship.

And boasteth great things. The design of the apostle is to illustrate the power and influence of the tongue. This may be done in many respects. The apostle does this by referring to its boasting; to the effects which it produces, resembling that of fire (James 3:6); to its untamableness (James 3:8–9); and to its giving utterance to the most inconsistent and incongruous thoughts (James 3:9–10).

The particular idea here is that the tongue seems to be conscious of its influence and power, and boasts largely of what it can do. The apostle doubtless means to convey the idea that it does not boast unjustly of its importance. It has all the influence in the world, for good or for evil, which it claims.

Behold, how great a matter a little fire kindleth! The margin reads: wood. The Greek word (ulh) means a wood, forest, or grove; and then firewood or fuel. This is the meaning here. The sense is that a very little fire is sufficient to ignite a large quantity of combustible materials, and that the tongue produces effects similar to that. A spark will kindle a lofty pile; and a word spoken by the tongue may set a neighborhood or a village "in a flame."