The Torah reveals a latent fear: despite our willingness to obliterate idolatry from the land, the Jewish people will then express a desire to "adopt" pagan worship-styles for the worship of God.
Our parsha, parshat Re’eh, marks the bridge in Moshe’s concluding speeches from a discussion of the essentials and fundamentals of Jewish belief to a discussion about the commandment and how they are to be performed. First, Moshe reminds the people of the importance of completely uprooting all of the remnants of idolatry in Canaan, and establishing a new, central place of worship where all the people can gather instead. The laws discuss the details of what tithes are to be brought to this place, and how even the act of eating meat is affected.
Afterwards, the Torah reveals a latent fear that underlies the entire enterprise – despite our willingness to obliterate idolatry from the land, the Jewish people will then express a desire to "adopt" pagan worship-styles for the worship of God - “How did these people serve their gods – I will do the same” (12:29-13:1). Ramban explains the fears as follows – Moshe wasn’t concerned that having invested so much energy in eradicating the Canaanite cults, the Jewish people would should express a desire to perform the same rites themselves. Instead, the fear was much more insidious - the Jewish people will justify and associate the destruction of the Canaanites due to the object of their worship (the gods they worshipped were not worthy), however, they would not realize that what was as abhorrent to Hashem was the method of their worship. The Torah, therefore, begs us not to make this mistake; indeed, "every manner of abomination which YHVH loathes did they do in worship of their gods..." (12:31). In other words, besides having a misguided approach to worship (worshipping nothingness as deities), the methods they used (including, as the verse states explicitly, child sacrifice) were hateful to God.
To prove this point, this warning is immediately followed by the injunction against adding to - or diminishing from - God's commands. The S'forno explains that we should not bring our own methods of worship - whether the result of our own creative thinking or adopting the behavior of other nations - into the worship of God, as we don’t know what is and what isn’t an abomination in God’s eyes. Chapter 13 continues with a list of three situations where the Torah commands us to withstand both the temptation to listen to and the temptation to show mercy to a person or group of our own people that wish to lead us astray – the false prophet, the “mei’sit” (seducer), and the city that commits idolatry. In all these cases the Torah exhorts us to show no mercy and to completely eradicate them from the face of the land.
Courtesy of Yeshivat Har Etzion - www.etzion.org.il