It is natural to feel afraid when you are entering into something unknown. Every adventure brings its own fears. If one wants to live without fears one can live only in the grave. That's how many people live: they only appear to be alive. They are breathing, they are doing their jobs, but it is not life.
Life is a constant adventure
Sannyas has two steps: First is from the known into the unknown, and the second is from the unknown into the unknowable. It is natural to feel afraid and there is no contradiction that you are also feeling happiness arise; that too is as natural as fear.
The person who lives without any adventure lives without fear but also without happiness. He lives a convenient life, comfortable, cozy, but dull, stupid, meaningless, with no joy, no song, no dance; nothing ever happens into his being, he simply vegetates.
From birth to death he simply goes on dying every day, each moment, slowly. Of course his death is so slow that he cannot feel it. It is a kind of slow suicide. People have chosen this kind of slow suicide just because they want to avoid all fear. This is avoiding life itself, and if you avoid life you are avoiding God. Somebody asked Mark Twain once, "What do you think are the three best things in life?"
Humorously, sarcastically, he said, "The first best thing is never to be born. The second best thing is to die immediately after birth. And the third best thing is to die as soon as possible." But his humor has a tremendous truth in it. That's your logic too, that's the logic of the average mind, that's the logic of mind as such.
Mind is very much afraid of the unknown because mind feels capable when you are functioning within the boundaries of the known. Mind means knowledge. You are acquainted with it. You know all pros and cons; you know what to do, what not to do.
You have passed through the same route so many times that now you can pass with closed eyes without any fear of stumbling into anything or falling or going astray. You can function like a robot. Mind consists only of the known.
The moment you start inviting the unknown in, the mind freaks. The mind says, "No, this dangerous. I am not willing." Don't listen to the mind because mind means past; dead it is, already dead and gone. - Osho Rajneesh