פן תנקש. אֻנְקְלוֹס תִּרְגֵּם לְשׁוֹן מוֹקֵשׁ, וַאֲנִי אוֹמֵר שֶׁלֹּא חָשׁ לְדַקְדֵּק בַּלָּשׁוֹן, שֶׁלֹּא מָצִינוּ נוּ"ן בִּלְשׁוֹן יוֹקֵשׁ, וַאֲפִלּוּ לַיְסוֹד הַנּוֹפֵל מִמֶּנּוּ, אֲבָל בִּלְשׁוֹן טֵרוּף וְקִשְׁקוּשׁ מָצִינוּ נוּ"ן, "וְאַרְכֻּבָתֵהּ דָא לְדָא נָקְשָׁן" (דניאל ה'); וְאַף זֶה אֲנִי אוֹמֵר "פֶּן תִּנָּקֵשׁ אַחֲרֵיהֶם" – פֶּן תִּטָּרֵף אַחֲרֵיהֶם, לִהְיוֹת כָּרוּךְ אַחַר מַעֲשֵׂיהֶם; וְכֵן (תהילים ק"ט) "יְנַקֵּשׁ נוֹשֶׁה לְכָל אֲשֶׁר לוֹ" – מְקַלֵּל אֶת הָרָשָׁע לִהְיוֹת עָלָיו נוֹשִׁים רַבִּים וְיִהְיוּ מַחֲזִירִין וּמִתְנַקְּשִׁין אַחַר מָמוֹנוֹ: פן תנקש [TAKE HEED TO THYSELF] LEST THOU BE SNARED — Onkelos renders תנקש as an expression of the same root and meaning as מוקש, a snare. But I say that he was not particular to examine carefully the expression, for we never find a נ in the term that means to snare, not even as a root letter that is sometimes omitted from it; but in the term denoting movement from place to place and knocking we do find a נ, as in (Daniel 5:6) “and his knees knocked (נקש) one against the other”. Here, too, I say that פן תנקש means lest thou run after them so that you cling to their doings. Similar is (Psalms 109:11) “Let the creditor be מנקש to all that he has” — he (the speaker) is cursing the wicked that he may have many creditors and that these may go about running after his money.
אחרי השמדם מפניך. אַחַר שֶׁתִּרְאֶה שֶׁאַשְׁמִידֵם מִפָּנֶיךָ, יֵשׁ לְךָ לָתֵת לֵב מִפְּנֵי מָה נִשְׁמְדוּ אֵלּוּ, מִפְּנֵי מַעֲשִׂים מְקֻלְקָלִים שֶׁבִּידֵיהֶם, אַף אַתָּה לֹא תַעֲשֶׂה כֵן שֶׁלֹּא יָבֹאוּ אֲחֵרִים וְיַשְׁמִידוּךָ (עי' ספרי): אחרי השמדם מפניך [TAKE HEED THAT THOU BE NOT SNARED] (according to Rashi, THAT THOU DO NOT RUN AFTER THEM) AFTER THAT THEY BE EXTERMINATED BEFORE THEE — The meaning is: after you see that I exterminate them from before you, you ought to pay attention to why these were exterminated — because of the depraved doings which they practiced. Consequently you should not act likewise lest others come and exterminate you (cf. Sifrei Devarim 81:3).
איכה יעבדו. לְפִי שֶׁלֹּא עָנַשׁ עַל עֲבוֹדָה זָרָה אֶלָּא עַל זִבּוּחַ וְקִטּוּר וְנִסּוּךְ וְהִשְׁתַּחֲוָאָה, כְּמוֹ שֶׁכָּתוּב (שמות כ"ב) "בִּלְתִּי לַה' לְבַדּוֹ" – דְּבָרִים הַנַּעֲשִׂים לַגָּבוֹהַּ, בָּא וְלִמֶּדְךָ כָאן שֶׁאִם דַּרְכָּהּ שֶׁל עֲ"זָ לְעָבְדָהּ בְּדָבָר אַחֵר, כְּגוֹן פּוֹעֵר לִפְעוֹר וְזוֹרֵק אֶבֶן לְמַרְקוּלִיס, זוֹ הִיא עֲבוֹדָתוֹ וְחַיָּב, אֲבָל זִבּוּחַ וְקִטּוּר וְנִסּוּךְ וְהִשְׁתַּחֲוָאָה – אֲפִלּוּ שֶׁלֹּא כְדַרְכָּהּ חַיָּב (סנהדרין ס'): איכה יעבדו HOW DID [THESE NATIONS] SERVE [THEIR GODS? EVEN SO WILL I DO LIKEWISE] — Because Scripture has laid down a punishment for idolatrous worship only in the case of sacrifice, offering incense, libation and prostration, as it is written (Exodus 22:19), “[He that sacrifices unto any god] save unto the Lord only [shall be doomed to death]” — which thus puts under the death penalty only kinds of worship that are performed in honor of the Most High God (i.e. such as have characteristics similar to “sacrifice”; cf. Rashi on Exodus 22:19), Scripture comes and teaches you here that if the usual way of worshiping any idol is by some other rite, as e.g., that one exposes himself in front of Baal Peor, or casts a stone before Mercury — then this is its cult and one who performs it is therefore liable to the death penalty, but for sacrifice, offering incense, libation and prostration one becomes liable to the death penalty even though this be not the usual way of worshiping it (Sanhedrin 60b).