Commentaries:
These two brief verses broadly cover conduct, motivation, attitude, and prioritizing one's life. To meet these qualifications requires "truth in the inward parts" (Psalm 51:6). A deceitful heart will never meet the standards because it does not operate from a foundation of godly integrity. David says in verse 5 that, humanly, he was shaped in iniquity. God, with our cooperation through faith, is ultimately the Creator of a pure heart in us, but it is a protracted process achieved by imparting a holy nature by His Spirit. This unites us with a holy Christ, with whom we fellowship, washing us in the blood of the Lamb so that with His aid we can mortify the flesh and live toward God, giving Him first priority in everything.
John W. Ritenbaugh
The Beatitudes, Part 6: The Pure in Heart
It is telling that the word "ascend" is in this verse—especially when we compare it with Hebrews 1:1-3, which describes Jesus sitting at the right hand of the Majesty on high. Here, in a similar manner, He is standing in the Holy Place.
Richard T. Ritenbaugh
Christ's Death, Resurrection, and Ascension
Other Forerunner Commentary entries containing Psalms 24:3:
Matthew 5:8