I used to consider the circular church calendar to be silly. Every year, the same thing on the same day. I sometimes got so that I knew the words to be read by heart. Why bother?
Now, I know why bother. For needed refreshment, for re-painting the weathered sides of my mind. I find the ideas and principles of Buddhism very helpful in living life. Most of the ideas I have learned are quite simple and I can probably state most of them from memory. But, I find the emotional charge of ideas, my commitment to them and enthusiasm for them varies. When I come across writing or video that repeats them or criticizes them or praises them, I get refreshed. I literally get that part of my mind and emotions recharged, as with a new coat of paint or new clothes. The process is very similar to listening to a sermon on a passage I have heard preached about before.
Each month, I change some, usually in ways I don't realize. I gain some new insights or new doubts, new resolutions or plans, aims or projects. Reading or seeing something I have read or seen before is actually being read by a different person, a new person with new ideas who notices things or makes comparisons that weren't made on the previous round.
It is not just religion or philosophy. Savings plans, recipes I want to try, trips I want to take have a different cast to them when I look them over from a different vantage point in time and aging. I have been energetic enough and wide-ranging enough that I have already done many good things. Many of the possibilities that I didn't take up are still good candidates for rejection. They don't fit me or my principles or my station in life. They aren't good investments for me. I will undoubtedly try some new things from time to time but getting refreshed in activities and thoughts I have been involved with before pays off very well.