“The king’s heart is like channels of water in the hand of the LORD; He turns it wherever He wishes.” (Proverbs 21:1)
“The ‘LORD’ is the only absolute Sovereign. Certainly God controls the hearts of all men (Prov. 16:9; 19:21; 20:24). But it may appear that kings, rulers and presidents hold absolute sway. They may even believe that they possess such power, yet they are ‘in the hand of the Lord.’ Their thinking, motives, inclinations and decisions are under the absolute control of God Himself.
By the king’s ‘heart’ is meant all his powers of reasoning, feeling and choice. These are ‘like channels of water.’ The expression describes small irrigation ditches used to bring life-giving water to otherwise unuseable land. The farmer directed the water by digging such ditches wherever he wanted and by then opening and closing the pathway for the water to flow (Deut. 11:10; Isa. 32:1-2). So too God ‘turns it [the king’s heart] wherever He wishes.’ He is able to make even the evil intentions of a man’s heart promote His glorious purposes (Psa. 76:10).
Scripture is filled with examples of such control by God over the hearts of rulers, particularly as they deal with His people and stand to influence His purposes: Abimelech (Gen. 20:6; Psa. 105:14-15), Pharaoh (Acts 7:10; Exod. 10:1-2), Artaxerxes (Ezra 7:21-23, 27), Tiglath-Pileser (Isa. 10:5-7), Cyrus (Ezra 6:22; Isa. 45:1-4), Nebuchadnezzar (Dan. 4:30-31, 34-37), Belshazzar (Dan. 5:22-28), and Pilate (John 19:11). This truth is affirmed throughout the Scriptures (Eccl. 9:1; Dan. 2:21; Psa.105:25; 106:46; Revelation 17:17).
Only God is absolute in His control. ‘There is no wisdom and no understanding And no counsel against the Lord’ (v.30).” (Proverbs: A Mentor Commentary, p.463)