Thus speaketh the LORD God of Israel, saying, Write for thee all the words that I have spoken to thee in a {a} book.

(a) Because they would be assured and their posterity confirmed in the hope of this deliverance promised.

Scofield Reference Notes

[2] Write

Three "writings" by Jeremiah are to be distinguished:

(1) This is impersonal--a general prophecy, and probably the earliest. Jer 30:1-31:40.

(2) The prophecy destroyed by Jehoiakim. Jer 1:1-36:23.

(3) The destroyed writing re-written doubtless the writing preserved to us. Jer 36:27.

Jamieson-Fausset-Brown Bible Commentary

2. Write . in a book-After the destruction of Jerusalem Jeremiah is not ordered as heretofore to speak, but to write the succeeding prophecy (Jer 30:4, &c.), so as thereby it might be read by his countrymen wheresoever they might be in their dispersion.

Matthew Henry's Concise Commentary

30:1-11 Jeremiah is to write what God had spoken to him. The very words are such as the Holy Ghost teaches. These are the words God ordered to be written; and promises written by his order, are truly his word. He must write a description of the trouble the people were now in, and were likely to be in. A happy end should be put to these calamities. Though the afflictions of the church may last long, they shall not last always. The Jews shall be restored again. They shall obey, or hearken to the Messiah, the Christ, the Son of David, their King. The deliverance of the Jews from Babylon, is pointed out in the prophecy, but the restoration and happy state of Israel and Judah, when converted to Christ their King, are foretold; also the miseries of the nations before the coming of Christ. All men must honour the Son as they honour the Father, and come into the service and worship of God by him. Our gracious Lord pardons the sins of the believer, and breaks off the yoke of sin and Satan, that he may serve God without fear, in righteousness and true holiness before him all the remainder of his days, as the redeemed subject of Christ our King.