Good point MondEgo about knowing rather than believing just because it is written.
I learnt early on that I wasnt alone when consciously venturing out. Starting from episodes within my house I had an experience where I was flung out through what I perceived as my bedroom window.
However I later came to understand that this was teaching me that once I've left body to get far away from it. In other words I was being taught.
When astral journeys started I was flying once near a high cliff and saw many black almost robot style human shaped people. I felt threatened when they saw me and got closer but it was fun as I just flew away.
As time went on I was put through fear scenarios but all you have to do is think 'Back to body now'.
Eventualy all my visits turned to lessons to do with my waking life. They were consciously induced out of body's but mostly there was an intelligence that was taking me somewhere for consideration, and it would turn out very meaningful.
So for me, I knew that I wasnt alone.
Any area or scenario that you find yourself in, all you have to do is will yourself back to body .
The golden rule of being in a peaceful state of mind when projecting I think is essential.