Psalms 120:4

4.The arrows of a strong man sharpened, with coals of juniper. Here the Psalmist amplifies in another way the malice of such as distress the simple and innocent by their calumnies, affirming that they throw out their injurious reports just like a man who should draw an arrow, and with it pierce through the body of his neighbor; and that their calumnies were like coals of juniper, (52) which penetrate more effectually, and burn more intensely the substances with which they come in contact than the coals of any other kind of wood. The amount is, that the tongues of these slanderers were inflamed with the burning heat of fire, and, as it were, dipped in deadly poison; and that such persons were the less excusable, from the fact that, without deriving any advantage from it, they were impelled by an unbridled passion to inflict upon others deadly mischief. As the Prophet records nothing here which he did not experience in his own person, it may be inferred that if it behoved him and men of a similar character to be assailed by their enemies with lies, which were to them as arrows to pierce them, or coals to burn them, we need not be surprised at seeing the most eminent servants of God exercised with similar assaults.

“Sharp arrows of a warrior,
And burning coals of juniper, thou resemblest.”

He, however, in a footnote requests the reader “to observe, that this is given as what seems to be the most probable interpretation of the passage, though it cannot be regarded as absolutely certain.”