psalm 24

Psalm 24:4:
He who has clean hands and a pure heart, Who has not lifted up his soul to an idol, Nor sworn deceitfully.

Read this way, someone who is “pure in heart” has a heart entirely devoted to God, a heart that is not mixed or divided or combined with anything else. Food that is “100% pure” does not have any additives or fillers. Hearts that are 100% pure are set on God and nothing else—no private agendas, not secret idols.

A heart that is set on God and God alone will see Him, both in this life and in the life to come. Only those who wholly put their trust in God and not idols or false gods will see Him face-to-face in glory when this life is over. But the Lord God Almighty truly is the king and head over all even now. He has created and sustains everything. In our modern, secular society we frequently make gods of science or progress, the economy or political process by explaining everything in their terms and making them our ultimate hope. And God does use them as His secondary agents. But when we reserve the ultimate place of explanation and authority and hope for God and God alone, we see Him and His work and His grace and goodness in all of life. And as we see our spiritual poverty, mourn our sin, and are made meek by awareness of our standing before God, we see that God alone truly is our only help and hope, and we cast off all other things. We hunger and thirst for a righteousness only He can provide. We show mercy as only He has shown mercy to us. And we purify our hearts of any rivals, so that we might see Him.  -Monergism
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