Ki Tisa contains the story of the EIGEL HAZAHAV, the golden calf. The episode of the golden calf was a great sin committed by the people of Israel. From the fact that 3,000 men were killed by the Leviyim who took up sword at Moshe’s “invitation”, we can conclude that the serious sin of idolatry (or whatever it actually was) was committed by less than a half of a percent of the adult male population. A much smaller fraction of a percent of the whole population.
But the secondary (let’s call it that) of fence-sitting on the part of the great majority compounded the offense to G-d – so much so that He spoke of destroying the entire nation. Whatever exactly happened, CHEIT HA-EIGEL was exactly that – a CHEIT, a giant sin.
Our goal in life is to honor and cherish the neshama that G-d places in us, by keeping His Torah in the best possible way. The beginning of Ki Tisa (the first 46 of its 139 p’sukim) is the end of the account of revelation at Sinai. Unfortunately, things went “off” right after that. We need/must do our share (and more) to set things right again.