From Nietzsche’s Gay Science:

The golden watchword. — Many chains have been laid upon man so that he should no longer behave like an animal: and he has in truth become gentler, more spiritual, more joyful, more reflective than any animal is. Now, however, he suffers from having worn his chains for so long, from being deprived for so long of clean air and free movement: — these chains, however, I shall never cease from repeating, are those heavy and pregnant errors contained in the conceptions of morality, religion and metaphysics. Only when this sickness from one’s chains has also been overcome will the first great goal have truly been attained: the separation of man from the animals. — We stand now in the midst of our work of removing these chains, and we need to proceed with the greatest caution. Only the ennobled man may be given freedom of the spirit; to him alone does alleviation of life draw near and salve his wounds; only he may say that he lives for the sake of joy and for the sake of no further goal; and in any other mouth his motto would be perilous: Peace all around me and goodwill to all things closest to me. — With this motto for individuals he recalls an ancient great and moving saying intended for all which has remained hanging over all mankind as a sign and motto by which anyone shall perish who inscribes it on his banner too soon — by which Christianity perished. The time has, it seems, still not yet come when all men are to share the experience of those shepherds who saw the heavens brighten above them and heard the words: “On earth peace, good will toward men.” — It is still the age of the individual.