Your search for "He who stops being better stops being good. - Oliver Cromwell 1599 - 1658" revealed the following:

RW-6.6 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

RW-8.8 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

RW-1.1 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best.  -  St. Jerome  347 AD - 420 AD

RW-7.7- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

RW-2.2 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD - Pretty Witty Mousepads Stop2Think

RW-5.5 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWK-6.6-Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWK-5.5-Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

YT-5.5- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

MW-1.1- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD - MugWisdom Ceramic 11oz

YT-6.6- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

DosQuotes MugWisdoms... Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. -vs- After all is said and done, more is said than done. - Which Wisdom Wins: Social or Sarcastic? - Ceramic 11oz cup

RW-4.4 - Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWK-2.2-Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWK-4.4-Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWK-7.7-Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

PWB-4.4- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

S2T- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD

YT-8.8- Good, Better, Best. Never Let it Rest, till your Good is Better and Your Better is Best. - St. Jerome 347 AD - 420 AD