v1-3: Introduction to the book. Josiah reigned for 31 years; Jeremiah began his ministry in his 13th year, continuing for 18 years during Josiah's reign. It seems Jeremiah was around 16 years old when he was called by God.
Jeremiah lived in Anathoth, where Abiathar had been exiled by Solomon, 1 Kings 2.26-27. Presumably, Jeremiah was descended from his family. Anathoth was part of Benjamin, a city given to the priests, Josh 21.18.
After Josiah’s death, Judah quickly declined, and was carried into exile 22 years later.
In total, Jeremiah ministered for the final 40 years before the defeat of Jerusalem, and (ch 40-44) for some years afterwards when the people took him into Egypt.
These verses indicate that the word of God came to Jeremiah in two distinct time periods; during the reign of Josiah, to strengthen the reforms he brought about; and during the reign of the final series of kings, to denounce the direction they were pursuing in rebelling against God.
v4-5: The word of the Lord came to Jeremiah; his calling, chosen by God for a specific task; "I formed you...I knew you...I set you apart...I appointed you." This is quite daunting, and a little frightening; but such a calling must enable us to endure all that the ministry involves. What we experience is no surprise to the God who called us.
The NT describes a call from God in similar terms, see John 15.16; Acts 9.15; 26.19.
v6:Jeremiah, being young, was reluctant to speak out; compare Moses (Ex 4.10), Samuel (1 Sam 3.1-5).
v7-8: The Lord's encouragement, "I am with you." Youth is no barrier (1 Tim 4.12). Jeremiah's responsibility was simply to obey. We see also that his message would not be instantly acceptable to everyone, yet the Lord God would give him strength to endure. A priest would commence his main ministry at age 30, yet Jeremiah was much younger, and would have looked down on someone so young. His message was specifically against the priests (v18).
v9-10: The Lord's commissioning, to speak His words with full authority. Jeremiah was set over the nations (v5 also), for his message would go beyond the borders of Israel, although his burden was mainly to speak to God's people.
There was no promise that the work would be easy, for the spiritual state of the nation was dire. The Lord God uses words from agriculture and construction to describe Jeremiah’s work; to root out and to pull down, to destroy and to throw down, to build and to plant.
v11-12: The vision of the almond tree, speaking of life and fruitfulness, as with Aaron's rod. The almond was the first tree to blossom; the Hebrew words means 'alertness,' or "watching." The message is clear, 'I am ready,' the time had arrived, Jerusalem was to receive the fruit of her actions.
Jeremiah had to learn to speak what he saw; see John 8.38; sometimes God's message is visual rather than verbal.
v13: The second vision is of a boiling pot, picturing judgment. The Lord explains the meaning of the vision.
v14: Calamity from the north, the route followed by the Babylonian army. Egyptians and others from northern Africa approached Israel from the south, Babylon and Assyria from the north.
v15: The thrones of northern nations placed in Jerusalem, being the capital city, and in other cities. This indicates defeat and servitude for Judah, as Gentiles began their domination. See Luke 21.24, where the Lord speaks of the "times of the Gentiles."
v16: There was good reason for these events, for Judah had been guilty of great wickedness and idolatry. This is a repeated theme, for they were slow to learn His ways.
v17: The command to Jeremiah, in the light of present sin and impending judgment. Get ready and speak all that is commanded (Matt 28.20), for we are not to change what God has said. We are not to neglect the unpalatable parts of the message.
Chapters 1-29 present Jeremiah's denunciation of Judah's sins.
v18: Jeremiah had to speak against the leaders, see ch 28, as well as to the people in general. He was given strength to stand, and to declare God's words.
v19: Conflict ahead, but also the promise of God's presence, as in v8. We need to God that God is with us.