Public Torah reading is the centrepiece of the Shabbat synagogue service. Most scholars claim that this practice was instituted by Ezra the Scribe when the people returned from exile in Babylon to re-establish the people’s connection to Torah. (See Nechemiah chapter 8 for the account of the first public Torah reading after the return.)
Maimonides argued that Moses introduced Torah readings on Shabbat, and also on Mondays and Thursdays so that the nation would not go three days without Torah.
There is a debate about the nature and purpose of public Torah reading. Is it a ritual that the reader accomplishes on behalf of everyone else present, or is it a public Torah study session? Rabbi Joseph Soloveitchik recalled that a congregant once asked his father, Rabbi Moshe Soloveitchik: “The Torah reader in our shul told me that he hates me and when he reads from the Torah, it’s for everyone in shul except me. Should I go to another shul to hear the Torah read publicly?” Rabbi Moshe answered that he need not – the weekly reading is a public Torah study session, which you fulfil by listening up and paying close attention to the words and their meaning.