Jeremiah 1:4

(Vers. 4, 5.) And the word of the Lord came to me, saying: Before I formed you in the womb, I knew you; and before you came forth out of the womb, I sanctified you: I have made you a prophet to the nations. Not that Jeremiah existed before his conception, as some heresy suspects, but that the Lord foresaw him to be. To whom things not yet made already exist, according to what the Apostle spoke: Who calls those things that are not, as those that are (Rom. IV, 17). But what is sanctified in the womb, we should understand according to the words of the Apostle: But when it pleased him, who separated me from my mother's womb, and called me by his grace, to reveal his Son in me; that I might preach him among the Gentiles (Galatians 1:15). John the Baptist is also sanctified in the womb, and receives the Holy Spirit, and is stirred in the womb, and speaks through the mouth of his mother (Luke 1). And when it is said, I have made you a prophet to the nations, it means that we are going to read about the prophet in him later, that he prophesied not only in Jerusalem, but also to many nations around.". Some understand this place to be about the Savior, who was specifically the Prophet of the Gentiles; and through the Apostles, he called all nations. For he was truly sanctified in the womb before being formed in the virgin womb, and before coming out of his mother's womb; and he was known to the Father, who is always in the Father, and in whom the Father is always.