John Calvin Commentary Jeremiah 46:20

"Egypt is a very fair heifer; [but] destruction out of the north is come, it is come." — Jeremiah 46:20 (ASV)

Jeremiah intimates here that though Egypt indulged in pleasures, it still could not escape the vengeance of God.

We reminded you yesterday why the Prophets mentioned the wealth, riches, and power of the ungodly: it is because they are blinded by all the good things in which they abound. For they fear nothing and feel no anxiety; instead, through a false notion, they exempt themselves from every evil.

Since, then, the unbelieving are so presumptuous and proud, the Prophets, on the other hand, warn them, saying that however much they may exult in their own strength and defenses, they would still, when it pleased God to make them prey, become the most miserable of all.

The Prophet, then, in short, takes away the false conceit of both the Jews and the Egyptians. It is as if he had said, “The Egyptians trust in their prosperity, as though they were like a heifer frisking in the fields; but calamity,” he says, “is coming, is coming from the north.” He repeats the same word to remove every doubt: coming, then, is distress, it is coming from the north, that is, from the Babylonians, who were situated north of Judea, as we stated yesterday.