John Calvin on Jeremiah 1:3-4

As to the beginning of his time and its termination, it has been briefly shewn, why he says that he had been chosen a prophet in the thirteenth year of Josiah, and that he discharged his office till the eleventh year of Zedekiah.

Now that Josiah is called the son of Amon, it is doubtful whether Josiah was properly his son. Amon began to reign in his twenty-second year, and reigned only two years. Josiah succeeded him in the eighth year of his age. If we number the years precisely, Josiah must have been born when Amon was in his sixteenth year; but it does not appear likely, that Amon was a father when he was sixteen years of age, for in this case he must have begotten a son in his fifteenth year; as the birth must have taken place nine months after. Then Josiah must have been begotten in the fifteenth year of Amon’s age. It is hence a probable conclusion, that he was a son by law and not by nature, according to what is afterwards said of Zedekiah, that he was Josiah’s son, because he was his successor, while he was, as many think, his nephew, a brother’s son. But it was a common thing to call the successors of kings their sons, who were their sons by law, and not, as I have said, by nature. It now follows-

Jeremiah 1:4-5

4. Then the word of the LORD came unto me, saying,

4. Et fuit sermo Jehova ad me dicendo,

5. Before I formed thee in the belly I knew thee; and before thou camest forth out of the womb I sanctified thee, and I ordained thee a prophet unto the nations.

5. Antequam formarem to in utero novi to, et antequam egressus esses e vulva sanetificavi to, Prophetam in gentibus constituite.