It's difficult to say really. I've had some experiences that I can only say came to me from an external source, but where from exactly, I never found out. In one situation in particular (I was being severely abused as a child) I was rescued from after obeying a message I received. Something very definite told me to do something, which I did, and I was then removed from the situation and my life was then safe. My faith believes in Guardian Angels, so perhaps I was helped from them. I knew that obeying the command would lead to me getting into a lot of trouble and would put me in danger, but I knew I had to do it and it led to something incredible beyond what I could ever have dreamed of.
Something also communicated me the date of my husband's funeral weeks before he died. I believe I was being prepared for his death. I asked repeatedly if the date was going to be the date of his death and the answer was "no", but that it was going to be a significant event and I needed to prepare. I didn't choose the date of his funeral, it was dictated by people travelling and the vicar's schedule. I wasn't a believer when this was happening to me I should add, but I was wondering why I was being told this date repeatedly and where it was coming from.
I've never been visited by Jesus though, which some people claim to have happened to them. I think that would be a nice thing to experience. My faith teaches us not to look for signs and wonders because we don't know where they've originated from and we can be fooled, but some things do make you wonder.
I did have a near death experience as a child - dark tunnel and everything. That was interesting. Scientists attribute these to brain chemistry and oxygen levels, but some people's accounts go far beyond those elements and are truly unexplainable by anyone's standards.
My present husband told me that he stepped into the road once whilst crossing and something grabbed his shoulder and pulled him back. A car then abruptly stopped and he would have been hit if he hadn't been pulled back onto the pavement. The driver was shocked because he'd fully expected to have hit him.
I hope nobody comes along and pours scorn on my experiences because of course they could all be imagined or have some explanation, but I am definite that they came from an external source and that they weren't merely my thoughts or musings.