זאת חקת התורה חוק של הוריות טומאה ובאחד בניסן ביום שהוקם המשכן נאמרה לפי שביום המחרת נשרפה הפרה להיות נטהרים לפסחיהם וקודם לכן לא יכלו לעשותה דבעינן והזה אל נכח פני אהל מועד וליכא. ואע״פ כן נכתב בה כאן לפי שהיו מהם טמאי מתים ממחלוקתו של קרח. זאת חקת התורה, “This is the statute of the law of the Torah;” The “statute” referred to here are the laws of ritual defilement and subsequent rites of purification. They were communicated to the people on the first day of Nissan, on the day the Tabernacle was erected ready for service. (Talmud, tractate Gittin folio 60). It had to be communicated on that day, as on the following day the red heifer, the instrument without which purification could not take place, was burned. Without knowledge of these procedures, the Passover, which would be offered on the fourteenth day of that month could not have been offered. The Torah had stipulated in verse 4 of our chapter that the location for the sprinkling of the waters containing the ash of that red heifer was opposite, i.e. facing the Tabernacle. It had to be inserted here as there were people, who as a result of the rebellion of Korach had become ritually contaminated.
אשר צוה ה' לא מצינו היכן נתפרשה מצוה זו במקום אחר כמו שפי׳ למעלה בפרשת בא. 'אשר צוה ה, “which the Lord had commanded;” we do not find where the Lord had commanded this previously, a phenomenon we referred to already in our commentary on Exodus 10,3.
ויקחו אליך לפי שנאמר אתה ובניך אתך תשאו את עון כהונתכם מגיד הכתוב שבגללן היא באה משלהם וכן כתיב ונתתם אתה אל אלעזר הכהן מתנה היא לו משל צבור. ויקחו אליך, “they shall bring to you;” seeing that the priests had been charged with ensuring that the Tabernacle precincts would not be breached by unauthorised Israelites, they had to be provided with the means to purify people who had violated these rules through ignorance or carelessness. This is also what is meant in verse 3, where G-d includes Elazar, Aaron’s, son as a recipient of this red heifer who is to attend to the ritual involving it. It is a gift to the priests from the community.