John Calvin's Bible Commentary
Jeremiah 42:15
He adds, Hear the word of Jehovah, ye remnant of Judah Jeremiah, by thus addressing them, no doubt endeavored to lead them to obedience. We indeed know that men in prosperity are in a manner inebriated, so that they are not easily induced to obey sound counsels. For whence comes it that kings and princes of the world indulge themselves so much, and allow such license to their lusts? even because the splendor of their fortune inebriates them. So also private men, when all things succeed according to their wishes, they lodge in their own dregs; hence it is that they are difficult to be ruled. The Prophet, on the other hand, shews that there is no reason for them to be proud. Ye are, he says, a small number, and God has wonderfully saved you. Hear, then, ye remnant of Judah In short, they are reminded of their humble and miserable condition, that they might be more teachable. But this also was done without any fruit, as we shall hereafter see.
This saith Jehovah of hosts, the God of Israel Of these words we have spoken elsewhere. God is often called the God of hosts on account of his power: so by this term God sets forth his own greatness. Afterwards when he is said to be the God of Israel, we know that the benefit of adoption was thus brought to the recollection of the people; for God had them especially as his people, and bound them as it were to himself. This ought then to have been a most holy bond of faithfulness and obedience. It was not, then, by way of honor that the Prophet thus spoke, but in order to reprove the Israelites for their hardness and ingratitude towards God. If, he adds, ye set your faces to go into Egypt, and ye enter in there to sojourn, it shall be that the sword which ye fear shall meet you, etc. Here is their punishment described, and there is nothing obscure in the words. God shows that they were greatly deceived, if they thought that they would be prosperous in Egypt; for no prosperity can be hoped except through the favor and blessing of God; and God pronounced a curse on all their perverse counsels when he saw that they would not be restrained by his word. If, then, we attempt anything contrary to the prohibition of God, it must necessarily end unsuccessfully; and why? because the cause of all prosperity is the favor of God, and so his curse always renders all issues sad and unhappy: and however prosperous at first may be what we undertake against God’s will, yet the end will be wretched and miserable, according to what the Prophet teaches here.