Always be prepared to defend your faith. This is your priority if time and circumstances allow. You have to realize that like any entity that claims truth over all others those others will challenge that truth, rightly or wrongly with legitimate or illegitimate grievances. Faith is hard, it is challenging and constantly challenged. If you are strong in your faith you will always be prepared for unprovoked attacks upon that faith by preparing yourself for a proper Christian response. Your attitude should be respectful (you don’t know the other persons circumstances which has caused them to bash your faith, they may be acting out of frustration of their own failures, ignorance, or a recent loss of a loved one for instance), you should attempt to give a reasonable rebuttal to the claims made if your able and they are responsive. Some people simply are not responsive in their current state of mind. If you are not able to respond reasonably because you cannot at the time formulate a rebuttal you should acknowledge the legitimacy of their argument and confess that you need to research further on the subject and would be pleased if you could get back to them on the matter. Sadly You must prepare yourself to ignore their response to this since most people at this point will believe themselves to be vindicated in their opinions and tell you as much since you have no rebuttal at the time or they are incapable of being receptive to one. It is simply the nature of being emotionally involved in ones arguments that this will be the case most of the time. One should make sure and make an attempt to get back to them if possible with a proper rebuttal. This is for you as much as them. Keep in mind most peoples demeanor in the earlier discussion or “bashing” episode will be reflective of their receptivity to your latter rebuttal and you should be prepared to accept this, at least you tried with a Christian spirit. Also keep in mind you are as human as they and are subject to the same attitudes that caused them to “bash” your faith in the first place. Try not to let this fog your reasoning ability, after all their grievances may just be legitimate.