Since I didn't comment on the whole of verse 6 I'd like to connect the second half of that verse with verse 7. If God's anger, (wrath as in John 3:36) falls on those who practice all kinds of sordid sins, isn't it quite obvious why Christians should not participate in these activities?! Let's be clear about something: Christ was judged on the cross for our sins and, thus, we have been saved from God's wrath. Romans 5:9b says, "...we shall be saved from wrath through Him." NKJV. However, if God will pour out His wrath on the unbeliever, you can be sure He will chastise the Christian who sins. Hebrews 12 has a great passage on the subject of God's corrective discipline for His children. Thank God He is not one to "withhold the rod of correction" when we need it! He disciplines His children because He loves them.
Our participation with the ungodly can rob us of an opportunity to witness to these same people. How can we encourage them to turn away from their sin if we do the same things?! But, does this mean we should never associate with sinners? Jesus sat down with tax collectors and notorious sinners. See Luke 15:1,2. Being with the unbelievers gave Jesus the opportunity to witness to them. He was criticized for it. But He didn't care about the criticism. He wanted to reach the sinner. Are you able to sit with the ungodly with the desire to win them to Christ? Are you willing to accept the criticism of well-meaning Christians when you do so?
There is a caution however. If you're weak with nagging temptations and if you're not staying in close fellowship with the Lord through His Word, prayer, and meeting with God's people, then you better avoid spending careless time with the unsaved who engage in immorality. Bad company can corrupt good morals.