David assures Absalom’s followers (2 Samuel 15:13–14) that God had set David apart, and would answer David’s prayers. Absalom wasn’t godly, nor was he the Lord’s chosen king of Israel. David was both godly and the Lord’s anointed king.
To be “set apart” for the Lord is to be distinguished by God as different from the ungodly. The concept of being “set apart” is the essential meaning of terms such as holy and holiness.
In the time of Israel’s slavery in Egypt, the Lord distinguished His people from the Egyptians. Exodus 8:22–23 contains the Lord’s message to Pharaoh. It reads: “But on that day I will set apart the land of Goshen, where my people dwell, so that no swarms of flies shall be there, that you may know that I am the LORD in the midst of the earth. Thus I will put a division between my people and your people.”
Today, as well, the Lord makes a distinction between His people and unbelievers. The apostle Paul writes in 2 Timothy 2:19: “‘The Lord knows those who are his,’ and ‘Let everyone who names the name of the Lord depart from iniquity.'”