Maran Ha-Rav Avraham Yitzchak Ha-Cohain Kook likewise explains that we relate with suspicion to anything new.To make what is new permissible, the way the Pesach Omer makes new grain permissible outside the Temple, and the way the Shavuot wheat offering makes it permissible in the Temple we need content. The content that makes the new permissible is the old, the light “in which G-d enveloped Himself, causing His majestic luster to shine from one end of the world to the other” (Bereshit Rabbah 3:4). This ancient light, stored away in the soul of Israel, will cause a new light to shine for us, a light that will illuminate Zion (Ma’amarei Ha-Re’eiyah, p. 182). In other words, there are some things that were forgotten over the course of the Exile, and “having once been forgotten, they are now being institutionalized once more” (Shabbat 104a and elsewhere). When we are forced to innovate, we do so using old content, as Rashi says, quoting our Sages on Devarim 11:13: “If you heed the old teachings, you will likewise heed the new teachings.” In order for the new to be viable, it must be attached to the old, and this is accomplished through in depth study (see Ikvei Ha-Tzon, p. 107).