The sharper
your chisel, the safer it is.
when you can apply less cutting force to the workpiece, you can keep better control of the chisel. Always place you chisels on a wood surface, never metal.
If your chisels have round handles and tend to roll off your bench, simply cut a flat into the handle and smooth it off with sandpaper.
Chisels can be works of art in their own right. Check out these chisels made in Japan by a master toolmaker.