What does kimu mean?
In the Talmud (Shabbat 88a) there is a lively discussion about the state of mind the Israelites were in when they received the Torah and entered into the covenantal relationship between the Jewish people and the divine. Imagine: a tribe of slaves, depleted and scared, wandering in the desert, encounters a mountain at which the voice of God booms amidst thunder and smoke, and bestows upon them a book of rules. According to one allegory in the Talmud, God held the mountain over the heads of the Jewish people and said, "accept the Torah, or this will be your burial." Our sages were bold enough to ask: was the initial covenant of the Jewish people entered into in coercion?
The sages in the Talmud continue to posit that thousands of years later, in the days of Purim, the Jews found pride in their Jewish identity and celebrated it joyously. The Talmudists lift this quote from the scroll we read on Purim: and the people "proactively arose, established and accepted - Kimu V'Kiblu" the Torah from a place of passionate volition (Book of Esther 9:27).
Kimu represents this idea — we inherited this tradition in various manners that we may or may not have chosen, but we have the freedom and privilege to arise and choose it willfully and from a place of deep personal joy.