For every kind of beasts, &c.— Instead of serpents, in this verse, some read creeping things. Dr. Doddridge renders it reptiles. Good men have through Divine grace governed their own tongues: otherwise their religion would have been in vain; ch. James 1:26. The comparisons mentioned in the context have led some to interpret the words thus: "That it is difficult for one man to subdue the tongue of another; more difficult than it would be for him to subdue a wild beast." But the apostle seems rather to speak of every man's governing his own tongue; and he could not look upon that as utterly impossible; for his whole design was to persuade Christians to govern their tongues. He does indeed represent it as a very difficult thing, in order to stir them up to a greater care and diligence: but if men could not possibly govern their tongues through the power of Divine grace, the evils which should arise from thence could not be their faults. The word 'Ακατασχετον, rendered unruly, is a metaphor taken from beasts that are with difficulty kept within bounds, by wall, or by hedges, or ditches.
Related Commentaries of James 3:7
James 3:7-8
7 For every kindd of beasts, and of birds, and of serpents, and of things in the sea, is tamed, and hath been tamed of mankind:
8 But the tongue can no man tame; it is an unruly evil, full of deadly poison.