Many times, we tend to be dogged with our perception of things, and go ahead to only see from our POV. Knowing the truth does not mean you must enforce the truth to someone. The best way to go about this is to accept the next person's emotions as valid and accept where they are coming from.
Take for instance, some acquaintances I have from church quarreled. Two females; one of them felt her lover was trying to dote on the other one, and made a fuss about the whole thing and making a scene in public; I was shocked maybe because I expect more from the individual and felt she should know better.
Some people were talking about it and were complaining about the whole issue of insecurity she displayed. I thought about it and felt the person in question has probably been heartbroken or doesn't feel confident in herself or loves herself dearly. We thought it best that she needs help in redefining what self-love is all about.
In that instance, the first truth was that the person in question isn't secure and thinks everyone will go for her lover, or her lover will go for some lady she probably feels threatened by.
Now the second truth is that there is a reason as to why she is insecure and needs to get help.
In essence, when the debate of what the truth is comes up, I think being empathetic helps a lot to understand the person's view. In case there is an instance of "erroneous truth", you try to understand and make them understand what you understand in a gentle way not as if to force it down their throat.
If you have the truth; my Lord Jesus and other truths about issues, don't force it down, it will make the truth lose its essence. Plus, emotions will now begin to cloud logic.
When you have a truth or opinion, especially if right, simply share in the most practical way by showing and not just telling so that they can easily see and believe your truths.
Go ahead and stand for the truth, let it set you free.