At Sinai the Bible relates that the Israelites “saw the voices” (Exodus 20:18). Why would it be important to emphasize that revelation was seen as well as heard?
The Kotzker Rebbe gives an astonishing answer. The Hebrew word “lo” can be written with an alef or a vav. When written with a vav, it means “to him” when written with an aleph it means “no” or “don’t.” Thus in Job the famous verse “Though He slay me, still will I believe (Job 13:15)” could, reading an alef rather than a vav, mean “If He slays me I will no longer believe.” Reading with an alef or a vav makes a big difference.
So, the Kotzker teaches, someone who heard “lo tignov” (“Do not steal”) as “lo” with a vav, would think the commandment is “steal for Him” — that is, that one is permitted to steal for God’s sake, for a holy purpose. Israel had to “see” the alef so they would not merely hear ‘lo tignov” and think that theft for a sacred purpose, such as to teach Torah, was ever permissible. The command is “do not steal.” Seeing the verses, Israel learned that theft was wrong, no matter its intent. The Torah knows that the criminal always claims nobility, but the crime is always base.