Jeremiah 29:3

‘By the hand of Elasah the son of Shaphan, and Gemariah the son of Hilkiah, (whom Zedekiah king of Judah sent to Babylon to Nebuchadnezzar king of Babylon), saying,'

His letter was sent by the hand of messengers who were going in Zedekiah's name to Nebuchadnezzar, no doubt with other more official correspondence. It is very probable that part of the aim was to renew Zedekiah's submission and assure Nebuchadnezzar of his loyalty, no doubt also delivering tribute. These would be prominent men, and may even have been the sons of Shaphan the Scribe (2 Kings 22:8), and Hilkiah the High Priest (2 Kings 22:4), although this is not certain. Elasah may have been brother to Ahikam who had aided Jeremiah (Jeremiah 26:24). This probably took place not long after the exile had begun in c.597 BC, at a time when Zedekiah had no thought of rebellion, and thus earlier than the previous chapter.