Let no man deceive you with vain words: for because of these things cometh the wrath of God upon the children of disobedience.
The world - and satan - are so ready to deceive us. The world itself is deceived. However, in John 3, we see the contrast of those who follow the deceit of this world and those who follow God in Christ Jesus.
"He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him." (John 3:31)
"He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God. And this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil. For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved. But he that doeth truth cometh to the light, that his deeds may be made manifest, that they are wrought in God." (John 3:18-21)
Light is come into the world, but not all men are obedient unto that Light. Those of us who have received the gift of salvation are spared the eternal wrath of God - but what sore punishment will we face if we, after receiving Light, turn around and live how we please? Perhaps we should remember the second of the Ten Commandments: "Thou shalt not take the name of the Lord thy God in vain; for the Lord will not hold him guiltless that taketh his name in vain." (Exodus 20:7)
Be not ye therefore partakers with them.
Because of all of this (vs. 5-6), Paul exhorts us to "Prove all things; hold fast that which is good. Abstain from all appearance of evil." (1 Thessalonians 5:21-22)
"Flee also youthful lusts: but follow righteousness, faith, charity, peace, with them that call on the Lord out of a pure heart." (2 Timothy 2:22)
If the work is darkness or associated with darkness, we must avoid it and flee. We are children of light - and must so walk (vs. 8).