Christian vs. Christian - The Guilty Conscious Decides?

Meet two people, both devout Christians:

1. Dave - No doubt in his mind. An exemplary Christian. Feels no problem with visiting a Temple or even participating in other religious events (where other Gods are worshipped). 

2. Jim - No doubt in his mind. An exemplary Christian. Refuses to even visit another religious event or participate or even view the worshipping of another God.

Are both Good Christians? Are both abiding by the Bible? Would both be blessed by Jesus all the same? This has been a MAJOR question for me as I engage in my research. I plan on visiting a Christian pastor soon to continue my research.

However, for now, a very good friend (a Christian) explained to me that:

"YES! Both are still good Christians as long as they have no guilty conscious or doubt of their belief in their one and only Lord, Jesus Christ."

Essentially, different Christians share a different view on their ability to SEE or ATTEND other religious events - even if they're just there for the sake of it. If they don't FEEL they are sinning (because they have a clean heart, they're not).

However, it IS a sin to try to push another into something they don't want to do. For So, Dave cannot judge Jim or try to force Jim to go.

The topic is still a bit confusing to me, however, apparently the Bible does not have a DEFINITE answer to this question. I'll find out soon...