The taboo.

One day I was walking past this church building I forgot where it was, probably the CBD. I saw this sign that said :

"SHHH don't say his name !"

It immediately got me thinking, why is there such a taboo on the name "Jesus"? Why does bringing his name up cause unease and results in getting deathstared by some people. It seems as if the only time the word 'Jesus' is acceptable in society is if someone is using it to vent their frustration/anger. Or maybe even the occasional "thank you Jesus", which in most cases is completely unrelated to the person's actual faith in Jesus. I remember in particular that when some Christians started talking about God/Jesus they'd specifically lower their voice to the point where no one else would be able to hear them. I used to be like that too. But for a believer:

"Whoever is ashamed of me and my words, the Son of Man will be ashamed of them when he comes in his glory and in the glory of the Father and of the holy angels."- Luke 9:26

I'm not 100% sure if ashamed means that Jesus will deny that person in front of his Father upon his second coming. But there is another similar verse which says (paraphrasing) If you deny me in front of men I will deny you in front of my Father. 

I guess I'm not 100% sure why there is such a taboo on Jesus, probably because most people don't want to talk about religion these days or something along those lines. Perhaps bringing his name up convicts people of whatever sins they've committed which they'd rather bury behind in their past. But my message to any believers would be that verse up there in bold. Jesus wasn't ashamed to get whipped and nailed onto a cross for you. So why are you ashamed to simply talk about him to your friends? Which one do you think would have been more painful and humiliating?