"How can we discriminate between favorable and unfavorable? We see that great spiritual teachers throughout history always support tradition while at the same time bringing about needed changes, or adaptations, in the details of how a spiritual culture is followed. These changes are made according to time, place, and the persons involved. While this may work when employed by spiritually evolved beings, how can the average person know when he or she is adapting in an inappropriate way or according to conditioning? In other words, how can we know how to not disturb the essence while changing details according to time and place? When one of my mentors, A.C. Bhaktivedanta Swami Srila Prabhupada, was asked this question, he said, “It is not an easy thing to know.” It takes a certain amount of spiritual advancement to know what can be changed and what cannot. It becomes important to understand what constitutes elevated consciousness, and thus what constitutes a proper leader. If we learn to recognize true visionary leadership, we can trust in the changes that are being made."
January 1, 1970
https://en.wikiquote.org/wiki/Bhakti_Tirtha_Swami