Christians tell other people about Jesus because he is real. He was a real man, who did a real man's job 2000 years ago. He died about the worth death possible at the hands of the Romans, the world experts in degrading execution.
He defeated death and the grave and lives today.
Many intelligent and expert sceptics with an open mind have set out to disprove Christianity and when they have really researched have changed their minds and have become disciples of Jesus.
The point is that, although many things in my life are important the most pivotal fact is that I am a follower of Jesus. This affects every other aspect of my life, (or it should) It affects my attitude towards other people, money, possesions, status, power, influence and how I spend my time.
Surely, in contrast, to an atheist there is nothing. If there is no God, no Jesus, there is nothing at the centre of your life, as there is at mine.
If that is the case surely there is no motivation to share that?
Trivial example: I am not interested at all in football. I have no desire to watch it or play it. Naturally, out of that fact, I have no desire to encourage other people not to like football. What would be the point of that?
Therefore I really don't understand it when 'atheists' are practically evangelical in there zeal to persuade people that there is no God. My theory on that (and of course this is a generalisation and I may be totally wrong) is that people like this, who are vehementaly opposed to the existance of God/Jesus really have the issue of anger or defiance towards Him.
I have friends who say that they're athesists and we have talked at great length on this topic. A couple of them have conceeded that they wish to deny the existance of God as if they acknowledge Him they would have a change the way they live their lives. I know that others blame God for bad stuff that has happened to them or others and I understand this, but surely it's disengenuous to say you don't believe in God because you're angry at/with Him?