Jeremiah 17:7,8 - Joseph Benson’s Commentary on the Old and New Testaments

Blessed is the man that trusteth in the Lord That lives in continual obedience to him, and relies entirely upon him for every blessing he wants for his body or soul, for himself or others who, under God, are dependant upon him; and whose hope the Lord is Who makes the Lord's favour the good he hopes for, and his power the strength he hopes in. Trusting aright in the Lord necessarily implies walking closely with him, and not departing from him in heart. For it is naturally impossible that any one should repose confidence in another for any thing which had been promised under a condition, without a consciousness in himself that he had, at least in some good measure, complied with the condition upon which it was promised. For he shall be like a tree planted, &c. He shall be prosperous and successful in his counsels and undertakings. He may be compared to a tree planted in a fertile soil, on the bank of a river, to which it extends its roots, and from which it derives abundance of sap and nourishment. And shall not see when heat cometh Ου φοβηθησετα οταν ελθη καυμα, say the LXX., shall not fear when heat cometh. They follow the reading of the Hebrew text, which is to be preferred before that of the margin. And shall not be careful in the year of drought Shall not be solicitous for fear it should lack moisture; that is, in a time when the leaves of trees standing on dry mountainous places are parched and withered, it shall retain its verdure, and continue to yield its fruit. Blaney translates the clause, “And it is not sensible when heat cometh; but its leaf is green, and in a year of drought it is without concern; nor doth it decline bearing fruit.”