From Paul Houses’s essay in the ESV Study Bible, which will be reprinted in the soon-to-be released Understanding the Big Picture of the Bible: A Guide to Reading the Bible Well:

The Prophetic Books include most of the OT’s greatest themes, preserving in written form for future generations the reasons Israel’s history happened as it did. Though the authors wrote in different times and under different circumstances, their messages are in theological harmony with one another and with other types of biblical books. Several interrelated ideas unify the prophetic message, making it possible for readers to find their bearings in some difficult literature. It is often helpful to decide which of the following themes the biblical author is stressing when one becomes puzzled by the content of the books.

First, the prophets assert that God has spoken through them.

They clearly considered themselves God’s messengers and heralds, for they repeatedly preface their messages with the phrase, “Thus says Yahweh.” In this way the prophets are claiming that their books are the written word of God. Peter explains that the prophets “were carried along by the Holy Spirit” (2 Pet. 1:21). Just as God used Moses to write and preach so that Israel could know God’s will in his era, so God used the prophets in their generations.

The prophets declared God’s instructions in two basic ways: word and symbol. Usually the prophets presented God’s word orally (e.g., Jer. 7:1-8:3) or in written form (e.g., Jer. 36:1-32) to varying types and sizes of audiences. Occasionally they performed symbolic acts that demonstrated God’s purposes. For example, Isaiah went naked and barefoot for three years to teach God’s people their future if they continued to seek help from other nations rather than from God (Isa. 20:1-6). Perhaps the saddest case of symbolic prophecy was Hosea’s marriage to unfaithful Gomer, which portrayed God’s relationship with unfaithful Israel (Hosea 1-3).

Second, the prophets affirm that God chose Israel for covenant relationship.

The Pentateuch (the first five books of the OT) teaches that God chose Abraham and his family to bless all nations (Gen. 12:1-9), that he revealed salvation by grace to Abraham (Gen. 15:6), and that he assigned Moses to write a record of this revelation (Ex. 24:4). Furthermore, through Moses in Exodus-Deuteronomy he revealed the lifestyle that reflects that relationship.

With these truths in mind, the prophets addressed Israel as a people with special responsibilities based on this special relationship (Jeremiah 2-6; Hosea 1-3; Amos 2:6-3:8; etc.). Through the prophets God revealed the success and failure of Israel’s attempts or lack of attempts to fulfill their confession of faith in God and their God-given role as a kingdom of priests charged with serving the nations (see Ex. 19:5-6).

Third, sadly, the prophets most often report that the majority of Israel has sinned against their God and his standards for their relationship.

They have failed to trust God (Isa. 7:1-14). Thus, they have broken the Ten Commandments (cf. Ex. 20:1-17 and Jer. 7:1-15; Hos. 4:2). They have worshiped other gods (Ezek. 8:1-18). They have mistreated one another and failed to preserve justice among God’s people (Isa. 1:21-31). They have refused to repent (Amos 4:6-11).

Of course, in these times there was always a faithful minority, called the “remnant” (see Isa. 4:3; 10:20-22; etc.), as the prophets’ ministries themselves demonstrate (see Hebrews 11).

Fourth, the prophets warn that judgment will eradicate sin.

This judgment is often called the “day of the Lord” (Isa. 2:12-22; Joel 2:1-11; Zeph. 1:7-18; etc.; see note on Amos 5:18-20). This is a day in history, as when Jerusalem was destroyed by Babylon (Jer. 42:18), but it is also a day to come, when God will judge all the world’s inhabitants (Isa. 24:1-23). The prophets recorded these warnings in writing so readers can do what the prophets’ original audience usually failed to do—turn from sin to God.

Fifth, the prophets promise that renewal lies beyond the day of punishment that has occurred already in history and beyond the coming day that will bring history as we know it to a close.

The coming of the Savior lies beyond the destruction of Israel and other such events. He will rule Israel and the nations, and he will bring peace and righteousness to the world (Isa. 9:2-7; 11:1-16). This Savior must suffer, die, and rise from the dead (Isa. 52:13-53:12). He will be “like a son of man,” and “the Ancient of Days” (God himself) will give him all the kingdoms of the world (Dan. 7:9-14). He will be the catalyst for a new covenant with Israel that will include all those, Jew or Gentile, whom God’s Spirit fills and changes (Jer. 31:31-40; 32:14-26; Ezek. 34:25-31; 36:22-32). This new people will serve him faithfully. Eventually he will cleanse the world of sin and recreate the earth (Isa. 65:17-25; 66:18-24; Zeph. 3:8-20). The creation now spoiled by sin will be whole again.