Jeremiah 21:2 - Matthew Poole's English Annotations on the Holy Bible

Zedekiah, as he was none of the best, so he was none of the worst, of the kings of Judah; be had some convictions and impressions (possibly from his education) not worn off; and having some reverence of God, he sends to the prophet to inquire of the Lord, because the king of Babylon was come up to make war against them. It is true, the greatest contemners of God and his faithful ministers will sometimes, in great straits, choose to send for them rather than those who in their prosperity pleased them. Hence we read of Saul, when he went to the witch at Endor, desiring that Samuel might be raised up. But in Zedekiah's whole story we read no such eminent contempt of God, but a disobedience to the commands of God, proceeding rather from his easiness to be ruled by his corrupt court, than from a stubbornness in himself. By mentioning God's former wondrous works, possibly he may have a respect to God's raising Sennacherib's siege in the time of his grandfather Hezekiah. The remembering of God's former wondrous works is of use to raise in us a hope and confidence in God for further deliverances, supposing ourselves under the same circumstances of obedience to God's will; otherwise not, as we shall see in the case of Judah and its king at this time; therefore Zedekiah saith, if so be. Guilt of sin hinders confidence and holy boldness in the best: but as the guilt is greater, so the hope or confidence of any is justly less.