Please clarify, because it depends on what you mean. Do you mean is it OK to keep your mouth shut when other people voice opinions that you believe to be immoral? Do you want to know whether or not you ought to stick up for your own way of behaving instead of violating your own standards of behavior in order to avoid criticism or having others take offense? Do you want to know when you are and are not bound to try to convert someone to the Gospel?
I need to be off-line for awhile, so at the risk of answering a question that I can’t follow up on, let me say this: You need to live the truth, but you do not have to throw pearls before swine. If no good is likely to come of opening your mouth, then it is OK to keep your mouth shut and mind your own actions. The Lord sent them out to preach, but he didn’t instruct even those with the preaching office to hammer on those who wouldn’t hear the Good News. He instructed them to shake the dust from their feet and keep moving. “
Do not give what is holy to dogs, or throw your pearls before swine, lest they trample them underfoot, and turn and tear you to pieces”.
Matt. 7:6. That is not being judgmental; it is just common sense. Likewise, you ought not set out to set others straight when you yourself have room for amendment. What you cannot do, however, is to set aside the truth you have been given in order to gain the acceptance of those who don’t see it or don’t accept it. You can, however, wait for the Holy Spirit to present someone to you before you give them a message they have shown they may not be ready to hear:
*Finally, all of you, be of one mind, sympathetic, loving toward one another, compassionate, humble. Do not return evil for evil, or insult for insult; but, on the contrary, a blessing, because to this you were called, that you might inherit a blessing. For: "Whoever would love life and see good days must keep the tongue from evil and the lips from speaking deceit, must turn from evil and do good,
seek peace and follow after it. For the eyes of the Lord are on the righteous and his ears turned to their prayer, but the face of the Lord is against evildoers. Now who is going to harm you if you are enthusiastic for what is good? But even if you should suffer because of righteousness, blessed are you. Do not be afraid or terrified with fear of them, but sanctify Christ as Lord in your hearts.
Always be ready to give an explanation to anyone who asks you for a reason for your hope, but do it with gentleness and reverence, keeping your conscience clear, so that, when you are maligned, those who defame your good conduct in Christ may themselves be put to shame. For it is better to suffer for doing good, if that be the will of God, than for doing evil. For Christ also suffered for sins once, the righteous for the sake of the unrighteous, that he might lead you to God. Put to death in the flesh, he was brought to life in the spirit. In it he also went to preach to the spirits in prison, who had once been disobedient while God patiently waited in the days of Noah during the building of the ark, in which a few persons, eight in all, were saved through water. This prefigured baptism, which saves you now. It is not a removal of dirt from the body but an appeal to God for a clear conscience, through the resurrection of Jesus Christ, who has gone into heaven and is at the right hand of God, with angels, authorities, and powers subject to him. *
1 Peter 3:8-22
Hope that helps.