I pretty much agree with most posters here re: the issue of fear.  There is another attribute that i wouldn't label fear, but maybe mindful and more emotionally detached caution, that i believe is a good attribute to develop and relates to humility somewhat.   

  While our most pervasive illusion and core belief is that we have limits, when we don't outside of the Law of Like attracts and begets Like, sometimes it's mindful to be aware of more probable limits. 

  For example, a somewhat immature Soul while concentrating its consciousness in the nonphysical dimension, to be more exact in the 4th major dimension, and in the 2nd next major sub plane within same, while planning for another physical life gets really ambitious.   

  It starts jumping up and down with enthusiasm and saying, "i want to do it all in this life, i want to balance much of my most difficult Earthly karma.   Hmmm, i will that challenge...that challenge...that challenge."   

  Meanwhile, that Soul's guide is looking on to the conditions, challenges, and physical life situations that that particular Soul is looking to take on.   The guide, being wiser, more patient, and intune than it's friend, knows that this Soul is looking to bite off a lot at one time, perhaps more than it can realistically chew considering its more innate and consistent patterns so far, and its major probabilities.   

   So, the Guide doesn't try to make it's *younger* friend fearful about those choices, BUT it sure does try to explain more holistically what this Soul is really getting itself into. 

Clears throat, "ahem, i know you are very excited about your spiritual progress and are getting more ambitious lately--which i'm glad about, but you might want to consider some of those conditions, and their intensity a little more...   It all seems a lot easier from here with this particular perspective, but once there, it can be a lot more challenging.  Believe me, i know from deep personal experience, and don't you as well, remember that life/time...?    Here, let me reshow you..." 

  At other times, it's important and perhaps even necessary to just "take the plunge" with no fear, worry, or even more detached caution in heart or mind.     In any case, deep, pervasive fear (particularly of the very emotionally centered kind) and worry is totally unnecessary and ever harmful to self and to others, and in those cases a conscious redirection to PUL, appreciation/gratitude, and/or the belief that nothing outside of you can harm your true eternal self is helpful.

  To some extent though, i agree with the Sage of Samos, aka Pythagoras, as well.  One of the many things he taught his students was "Of thyself, stand most in fear", though he was not one who advocated fear in general.   I think he was saying that we can inflict Soul wounds (imbalances!) on ourselves more than anything outside of us.   

  So, like most things pertaining to Earth living, its not a black and white issue.

they took a survey once to find out the biggest fear most people have.

I found it interesting it wasn't death. death came in 2nd to speaking in public.

It used to be that at times I would feel a background of fear. I didn't know why. I figured it was just some primal thing, partly based on not knowing what's out there.

Eventually, after making contact with spirit guidance, I found that I never got over my fear of things such as demons and possession. A fear that started after I saw the Exorcist. For years I suppressed this fear and didn't believe it was a concern. It turns out I had an aspect of mind I never took care of.

A time came where my spirit guidance determined it was the right time to help me get over this fear. It helped me in various ways, with different kinds of experiences. I also put a lot of effort into it. Right now I'd say I'm about 98% free of this fear.  I no longer feel a background of fear. This has gotten rid of heart chakra blockages and allows me to feel more love.  I've found that the way to get over a fear, is by examining the ideas that causes a fear to be.

So why the remaining 2%?  Because I still haven't gotten around to living 100% according to universal mind, rather than opinionated mind, nor do I allow myself to live according to love completely.  I've found that when I'm feeling a lot of love, it is hard to be afraid.

Some people might say it is a catch 22 situation. You can't feel more love if you don't let go of fear, and you can let go of fear, if you don't feel love. "NONSENSE!!" What you do is make the choice to let go of fear and open to love at the same "time."