There is, of course, a standard that the bible explicitly demands from us: in your hearts regard Christ the Lord as holy, always being prepared to make a defense to anyone who asks you for a reason for the hope that is in you; yet do it with gentleness and respect, having a good conscience, so that, when you are slandered, those who revile your good behavior in Christ may be put to shame. 1 Peter 3:15-17
I see many Christians who are ready to make a defense, but I also see very few Christians (myself included) who do it with "gentleness & respect." We all need to remember that once (I'm speaking to believers) we were ignorant to the Truth. We all once walked in darkness, succumbing to the temptations of sin and lawlessness. We hated our Creator and God's wrath abided on us. When we forget our former state, then how can we possible minister to an unbelieving world? Let us remember what we've been saved from!
I also want to say that "gentleness & respect" does not mean covering up God's Truth. Some things are hard to hear. Yes, it is sometimes difficult to share the Gospel, but trying to be "seeker sensitive" is blasphemy itself. There is no reason to hide the Truth of the bible. Remember, it is God who saves. We can be confident that when we share the sacrifice Jesus made, His call for us to die, the depravity of our minds, the consequences of our sin, etc. etc. that God's elect will come forth. We do not need to hide anything!
And lastly, I just want to state that correct theology is important: so that we may no longer be children, tossed to and fro by the waves and carried about by every wind of doctrine, by human cunning, by craftiness in deceitful schemes. -Ephesians 4:14
So please, stand up for God's Truth, glorifying Him in a way that leads men into repentance. Let us not forget our former ways of unrighteousness, but let the Spirit of God so transform us that the words out of our mouths and the meditations of our hearts would be pleasing to God, our Rock and our Redeemer. (Psalm )