Jeremiah 9:4-6 - Joseph Benson’s Commentary on the Old and New Testaments

Take ye heed every one of his neighbour Or, of his friend, as רעהו rather signifies; of him who pretends friendship to him, or whom he has befriended. And trust ye not in a brother Against whom you must stand as much upon your guard as if you were dealing with a stranger. For every brother will utterly supplant Will deceive, overreach, and take all possible advantage of his nearest relation; and every neighbour Or friend, rather, as before; will walk with slanders Will not care what ill he says of another, though never so false. The Hebrew, רכיל יהלךְ, is properly, will go about as a detracter, or calumniator, namely, carrying slanders with him from house to house. This is a strong description of the falsehood and calumny which universally prevailed among them. And weary themselves to commit iniquity They are so inclined and enslaved to iniquity, that they not only commit it when they can do it easily, but when the commission of it is attended with difficulty; for they take more pains to carry on their ill designs than the practice of truth and integrity would cost them. Thy habitation is in the midst of deceit That is, all about thee are addicted to it, therefore stand upon thy guard. They are God's words to the prophet. If all around us are false and deceitful, it concerns us to beware of them, and to be wise as serpents. Through deceit they refuse to know me, saith the Lord “The knowledge of God, which is true religion, is incompatible with the practice of any wickedness. And therefore it is natural enough for those that are resolved at all events to abide in their evil courses, to endeavour, if possible, to divest themselves of all religious principles, which, if insufficient to restrain, will be sure at least to be very troublesome to them.”