You tell your truth, which may or may not be the “real” truth. Ignorance is just as real there as it is here. If the person you are speaking to is perceptive enough, they’ll be able to see exactly where your truth is coming from, in the language of correspondences.
There is another way of looking at it. In the spiritual world, your inner nature becomes all of you. Often times during life various things conspire to keep us from expressing ourselves fully. These things disappear when we leave this world and with it goes any reason to be duplicitous.
Most people have not been transparently good or evil in their lives, so there begins a process of discovering one’s true nature. And well, like attracts like, and you’ll become surrounded with others like yourself. With no reason not to, you find your full authenticity and deception just loses meaning and purpose.