For additional notes and resources check out Douglas’ website.

Salient points:

• V.1 alludes to the irrigation canals common in the Middle East. The king's heart is in the hand of the King of Kings -- the only being with true and absolute sovereignty.
• Religion alone isn't enough (v.3). This emphasis on the heart is prevalent in all three divisions of the Old Testament -- Torah, Prophets, Writings.
• Hedonism will impoverish us (v.17). Work is what brings the profit (25). Living for pleasure isn't life at all (but death, according to Paul in 1 Tim 5:6).
• Impulse control (v.20). Guilty of gluttony? Applications: diet, sexual abstinence, drinking, exercise, expression of anger, and more.
• Discipline over our words (v.23).
• V.23 is an example of Hebrew rhyme (less important than parallelism, but still present here and there): Shōmēr pīv 'ûlshôlnô shōmēr mitsārôth naphshô. 
• Don't place all your hope in human planning: your own or someone else's. God is the one in ultimate control (30-31).

Challenge:

• Hand your eating over to the Lord.
• Gluttony is a serious sin in our culture.
• Obesity discredits the gospel.
• Eating with wisdom brings longer life, better health, greater alertness, greater ability to engage in various activities, and increased credibility as an ambassador of Christ.

Next Up: Chapter 22.