Setting The Record Straight
It is interesting to note that the word, ויקהל, appears twice in close juxtaposition to one another.
The word is used with the pronunciation of “Vayikahel,” that they were gathered on Aharon, to demand that he build the Golden Calf.
The second time it was pronounced, “Vayakhel,” where Moshe gathered the עדת ישראל, “the congregation of Israel.” The Alshich wrote that Moshe Rabbeinu excluded the Eirav Rav, the mixed multitude, who were the instigators of this terrible sin.
Moshe gathered the nation to set the record straight as to their future. It was clear that the construction of the Mishkan was meant to be an atonement for the sin of the Golden Calf.
He wanted to reiterate the importance of Shabbat observance. Even though the construction of the Mishkan was a spiritual endeavor, Shabbat took priority. No work of any kind could be done on this day.
The Alshich further noted that there were thirteen different gifts brought in the construction of the Mishkan. This number had a double meaning. The number “thirteen” was equal to the word, ״Echad,” reflecting oneness and unity. It also was meant to show that there was a greater number of gifts and materials used for the Mishkan, than that was used in the Golden Calf.
All of this was an effort by Moshe to get the Jewish people back on track. They needed to get their priorities straight. They had to separate from the troublemakers, and focus on their role of bringing morality and sanctity to the world.