A Muslim may say:
The Christian West is an immoral place. Christians have sex without marriage, they drink Alcohol and use drugs and practice homosexuality.
First, this is a wrong impression, the West is not Christian. The West has a lot of religions and ideologies. Those who are true Christians who lives in the West do not practice such sins.
Someone who carries the religious label of Christian is not really Christian unless he/she follows the path of Christ.
For example, in the Muslim world, there are a lot who are so called Muslims who do not pray or fast, they practice sins like drinking alcohol and sexual immoralities. Can I say that Muslims drink alcohol and have sex without marriage; because I have observed some unfaithful Muslims practicing these sins?
Let me show you few verses from the Bible which actually command the believers to not practice such sins.
“And do not get drunk with wine, for that is debauchery …” (Ephesians 5:18)
“You shall not lie with a male as with a woman; it is an abomination” (Leviticus 18:22)
“But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.” (Matthew 5:28)
“Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God.” (1 Corinthians 6:9-10)