Scripture plainly reveals that God repeatedly calls for His people to separate from the world. This separation extends to every aspect of life, especially including the marriage bond. Why? Because God knows the very real danger that unbelievers pose to believers by drawing them away from Him (Deuteronomy 7:3-4; Judges 3:6-7; 1 Kings 11:2). This is why God specifically instructed His people in both the Old and New Testament to marry among themselves (Jew with Jew and Christian with Christian). The nation of Israel was forbidden to yoke up with the surrounding nations because Israel would adopt heathen practices and the worship of false gods (Exodus 34:15-16). Though God’s commands for the New Testament believer are often different from His plan for the Jew, in this aspect they remain constant and unchangeable.
Believers should seek to be pure in every facet of life. One might consider limiting this to the places he goes or the things he hears and sees, but purity demands a much greater focus. Believers ought to think on pure things (Philippians 4:8) with pure minds (2 Peter 3:1) and pure consciences (1 Timothy 3:9; 2 Timothy 1:3). In particular, believers should have pure hearts before the Lord (1 Timothy 1:5; 2 Timothy 2:22). A pure heart will lead to a pure conscience and a pure mind. A pure heart changes where a man goes, what he looks upon, and the things he allows to enter into his ears. Every Christian should strive to make sure that all things are pure.
