The books of some of the prophets provide some clues to the answer to our question. 'The Lord said to me, "Take a large piece of writing material and write on it in large letters: Quick-Loot-Fast-Plunder"  (Isaiah 8: 1). 'In the fourth year that Jehoiakim son of Josiah was king of Judah, the Lord said to me, "Get a scroll and write on it everything that I have told you about Israel and Judah and all the nations" , (Jeremiah 36: 1-2). 'The Lord gave me this answer, "Write down clearly on clay tablets what I revealed to you, so that it can be read at a glance. Put it in writing, because it is not yet time for it to come true. But the time is coming quickly, and what I show you will come true. It may seem slow in coming, but wait for it; it will certainly take place, and it will not be delayed”, (Habakkuk.Z: 2-3). 'God told me to write down in a book what people are like, so that there would be a permanent record of how evil they are' (Isaiah 30: 8).

It was revealed to these prophets that the words which they had spoken, and which communicated the will of God to others, should be written down so that those who had not heard what was said would also be able to know God's will, through reading what was written. The messages which came to the prophets expressed in human thought forms what was the will of the eternal, almighty God. These messages therefore had an abiding value beyond their immediate spoken context. The passage from Habakkuk indicates that fulfillment of a prophecy could be delayed in time but there was no doubt that when the will of God had been made known to men and had been expressed in terms that could be understood in human thought, fulfillment of what had been spoken would eventually come. The prophet spoke, but it was God who acted according to his purposes.

We may now say that what impelled those who preserved the words of the prophets in writing was their conviction that the abiding will of God was expressed in the spoken human words of the prophet.

Although the activities and utterances of each prophet should be studied against the situation in which he lived, we can summarize some significant points which characterize their behaviour and preaching: