I can understand "religious symbols" practically every religion has them, Christianity has the "Cross", Catholicism has the "Virgin Mary" and "rosary...

I can understand "religious symbols" practically every religion has them, Christianity has the "Cross", Catholicism has the "Virgin Mary" and "rosary beads" and the Daoist have symbols such as "yin and Yang". These symbols help people associate different religions. You speak of "religious truth" but doesn't every religion have their own truth? If words and concepts are considered to be vulnerable and people can`t stand firmly on the 'religion" they claim then how secure is their faith? Not everyone claims their is a G-D but we consider them to be fools but wouldn't we be considered the fools for arguing with someone when we know the truth or what we perceive to be our truth. 

Can anyone help me with this? Give me an advice to answer bolded question?