a cryptoquip

I got this passed to me from my dad this morning. Just remember what he told me, “I don’t promise greatness. Just interest.” The following is a Robin Hood quote:

R'N TVGGRMT NZIIRVW. R DZMG GL YV ZM RM-OZD, MLG ZM LFGOZD.

I’ll post the answer in about a day, unless somebody posts it first.