Michaela has said it wonderfully well.

It is perhaps the most "painful" aspect of awakening to this knowledge that you cannot assert it (no matter how hard you try) onto people that really need it. The same Law of Attraction that prevents unwelcome influences in your own life, if you are not a vibrational match to them, also prevents (what you perceive) as welcome influences into the lives of others.

If others are not ready, they just won't hear what you are saying in the way you mean it. And the harder you try to convince them, the more they'll try and defend their own limitations.

The best you can do is be a supreme example of the principles in action and wait for people to ask you how you do it.

But sometimes even that isn't enough...

My own parents are strict orthodox Muslims who are in gradually declining health and mental states mainly brought on by their own restrictive religious beliefs. They won't accept my help in any form and they've long since decided I've been possessed by the devil or whatever their equivalent is. And, on the relatively rare occasions we do meet up, they attribute my ever-growing vitality, wealth and happiness (and all the lucky things that happen to me) as God building me up before he knocks me down again as punishment to teach me a severe lesson.

On the other hand, if I was miserable, in failing health and living in poverty, they would say also that it was God's punishment.

Sometimes you just can't win. :)

"When the student is ready the teacher will appear" - You can't get through to anyone if they're not ready and if they're not asking.

When we find something that has such a positive effect on our lives, our first impulse is to want to go and share it with everyone. However, we soon learn that just because we are ready for the lessons not everyone else is.

As you pointed out a lot of people are so conditioned due to their religious choices, that they really cannot hear what you are saying because they hold steadfastly to their own beliefs being The Truth. Until someone spends time expanding their awareness and opening their mind to new possibilities, they probably won't be able to hear what you're saying. That's okay too because you have to accept that everyone is where they're supposed to be on their journey right now, and if and when they are ready to awaken, the right teacher will appear.

I never told anyone I know in person (well, maybe one time) about the law of attraction. I simply do not know any people that are into this stuff.
The problem with teaching the law of attraction to others is that they lack faith. They will never empirically experience this because they do not believe this would work. Even if they are told that their strong belief is needed to make law of attraction work and they will try to believe, in the inside they will still doubt it and success won't come. It really easy to make mistakes when you are new into manifesting and become discouraged.

From my own experience, there is nothing that you can teach someone if they don't wish to learn... You are usually taken as a conceited know-it-all and you end up asking yourself "why didn't I shut up if no one asked for my opinion???!"

As Stingray says, all you can do is wait for people to ask you.