For your obedience is come abroad unto all men. I am glad therefore on your behalf: but yet I would have you wise unto that which is good, and simple concerning evil.(Romans 16:19) 
 

Simple Concerning Evil:
This Biblical principle is in direct opposition to the idea advocated by some, that children of Christians should be exposed to sin, immorality, ungodliness and the things of Satan in order to learn to confront temptation. Some suggest that children need not be guarded from ungodliness. However, according to Biblical revelation, this philosophy is not only against God's will, but is compatible with Satan's own desire that everyone be exposed to the knowledge of good and evil (Genesis 3:5). 

Knowledge of evil, along with continual exposure to Satan's ways, will lead many from the path of faith and obedience. Lot found this out to his deep sorrow when he lost his family (Genesis 13:12-13; 19:1-38). Scripture warns that ...evil communications corrupt good manners (1 Corinthians 15:33), and that Jesus Christ ... Who gave himself ...that he might deliver us from this present evil world... (Galatians 1:3-4). Those who advocate exposing children to an ungodly environment and/or influence are in danger of violating Jesus' warning in Matthew 18:6. 

Believers should do all in their power to keep their children from being exposed to sin's deceitfulness and the perverseness of this generation. To refuse to protect our children disregards the Holy Spirit's desire that they be innocent about what is evil. 
 

Being Separate from the World:
Be ye not unequally yoked together with unbelievers; for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness? And what concord hath Christ with Belial? and what part hath he that believeth with an infidel? And what agreement hath the temple of God with idols? for ye are the temple of the living God; as God hath said, I will dwell in them, and walk in them; and I will be their God, and they shall be my people. Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing... 2 Corinthians 6: 14-17. 

Blessed is the man that walketh not in the counsel of the ungodly, nor standeth in the way of sinners, nor sitteth in the seat of the scornful (Psalms 1:1). Parents bless their children by keeping them away from "the counsel of the wicked" and "the way of sinners." 

Don Stamp's commentary in the Full life Study Bible stated the following in his note on this verse: 

In God's eyes people ultimately are divided into two categorizes: Those in Christ and those who are not in Christ. Therefore, believers must not be in voluntary partnership or in intimate association with unbelievers, for such a relationship can corrupt their relationship with Christ. This includes a partnership in business, secret orders (lodges), dating, marriage, and close friendships. A Christian's association with unbelievers should be only as is necessary for social or economic existence, or to show believers the way to salvation. 

The concept of separation from evil is fundamental to God's relationship with His people. According to the Bible, separation evolves two dimensions-one negative and one positive: (a) separating yourself morally and spiritually from sin and everything that is contrary to Jesus Christ, righteous and God's Word; (b) drawing near to God in a close intimate fellowship thorough dedication, worship and service. 

In the Old Testament, separation was an ongoing requirement for God's people (Exodus 23:24; Leviticus 20:22-26; Isaiah 52:11). They were expected to be holy, different and separated from other peoples in order to belong to God as His very own. In the New Testament, God commanded separation of the believer (a) from the corrupt world system and from unholy compromise; (b) from those in church who sin and refuse to repent (Matthew 7:15; 1 Corinthians 5:9-11); and (c) from false teachers, churches or cults that teach theological error and deny Biblical truths (Matthew 7:15; Romans 16:17). 

Our attitude in separation must be one of (a) hatred toward sin, unrighteousness and the corrupt world system, (b) opposition to false doctrine, (c) genuine love towards whom we must separate from, and (d) fear of God. 

The purpose of separation is that we as God's people might (a) persevere in salvation (1 Timothy 4:16; Revelation 12:14-17), faith (1 Timothy 1:19; 6:10; 20-21), and holiness (John 17:14-21; 2 Corinthians 7:1), (b) live wholly for God as our Lord and Father (Matthew 22:37; 2 Corinthians 6:16-18), and (c) convince the unbelieving world of the truth and blessings of the gospel (John 17:21; Philippians 2:15). 

If we separate ourselves properly, God Himself rewards us by drawing near with His protection, blessing, and Fatherly care. He promises to be everything a good Father should be. He will be our Counselor and Guide; He will love and cherish us as His own children (2 Corinthians 6:16-18). 

The refusal of believers to separate themselves from evil will inevitability result in loss of: fellowship with God (2 Corinthians 6:16), acceptance by the Father (6:17), and our rights as children (6:18 Romans 8:15-16). 

In the "world," believers are aliens and strangers. They must come out of the world, not be conformed to the world, not love the world, overcome the world, hate the world's evil, die out to the world, and be delivered from the world (1 John 2:15). 

We must separate ourselves completely from the world and purify ourselves ...from all filthiness of the flesh and spirit, perfecting holiness in the fear of God (2 Corinthians 7:1). 

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