To not turn after the worship of idols — not in thought, not in speech and not in vision: To not turn after idolatry with thought or speech and not even only with sight; so that he not come from this to serve it, as it is stated (Leviticus 19:4), “You shall not turn to the idols.” And they, may their memory be blessed, said in Sifra, Kedoshim, Section 1:11, “If you turn after them, you make them gods”; meaning to say, if you involve yourself with their matters — meaning to ponder after the follies that those that believe in them say about it, that constellation x or star y does this action, and so [too,] incense x or service y; or you constantly observe the forms that their worshipers make in order to know the manner of its worship. All of this [can cause] you to be seduced after it and that you would worship it.
And explicitly is it stated there in Sifra, Kedoshim, Section 1:10 that even observing alone is prohibited — as they said there, “Rabbi Yehudah says, ‘Do not turn, to see them.’” And the matter is from the reason that we said, which is that it causes [one] to see it and to stray after it. And also, so that he not waste a portion of [his] time and be involved in these vanities, whereas man is only created to be involved in the service of his Creator. And this is what they, may their memory be blessed, said in Shabbat 149a in the chapter [entitled] Shoel Adam Mechavero, “And [regarding] an image itself, even on a weekday it is prohibited to stare at it, because it is stated, ‘You shall not turn to the idols.’ What is the inference? Rabbi Yochanan said, ‘“Do not remove God (Al tefannu El” a play on the words of the verse) out of your minds.’”
And this negative commandment — meaning, the prohibition of thought about idolatry — is repeated in another place, as it is stated (Deuteronomy 11:16), “Guard yourselves, lest your hearts be seduced and you serve, etc.” [This is] meaning to say that if your heart spends much time in thinking about it, it will be a cause to divert you from the straight path and to be involved in its service. And it is also stated about this matter (Deuteronomy 4:19), “And lest you lift your eyes to the heavens and see, etc.” As the content [of this verse] is not that a man not lift up his eyes to the sky and observe the heavens, but [rather] the intention of the thing is that he not observe them with his heart’s eye — to know their power and their makeup in order to serve them. And [it is] like it is stated in another place (Deuteronomy 12:30), “and lest you inquire of their gods, saying, ‘How do these nations serve their gods, and I will do so, me too, etc.’” The verse prevents us from asking about the manner of their worship, since all of this is a cause to err about it.
The laws of the commandment and its details are elucidated in many scattered places in the Gemara, such that they, may their memory be blessed, warned us about it, not to ponder thoughts of idolatry (i.e. Berakhot 12b); and they, may their memory be blessed, said that it is not only the thought of idolatry that is forbidden, but rather any thought that causes a person to uproot something from the Torah. And Scripture prohibited this explicitly, as it is written (Numbers 15:39), “and you shall not stray after your hearts.” And they, may their memories be blessed, said (Kiddushin 40a) that for Israel, the Holy One, blessed be He, does not consider a thought of sin to be like the act — except for the thought of idolatry, which is considered for a man to be like the act. (See Mishneh Torah, Laws of Foreign Worship and Customs of the Nations 2.)
And this prohibition is practiced in every place and at all times by males and females. And one who transgresses it and turns after idolatry in a way that there be an act [involved] with it, is lashed. (See Mishneh Torah, The Sanhedrin and the Penalties within Their Jurisdiction 19:4.)
שֶׁלֹּא לִפְנוֹת אַחַר עֲבוֹדַת אֱלִילִים לֹא בְּמַחְשָׁבָה וְלֹא בְּדִבּוּר וְלֹא בְּהַבָּטָה – שֶׁלֹּא לִפְנוֹת אַחַר עֲבוֹדָה זָרָה בְּמַחְשָׁבָה אוֹ בְּדִבּוּר וְלֹא אֲפִלּוּ בִּרְאִיָּה לְבַד, כְּדֵי שֶׁלֹּא יָבוֹא מִתּוֹךְ כָּךְ לַעֲבֹד אוֹתָהּ, שֶׁנֶּאֱמַר (ויקרא יט ד) אַל תִּפְנוּ אֶל הָאֱלִילִים. וְאָמְרוּ זִכְרוֹנָם לִבְרָכָה בַּסִּפְרָא (קדושים א יא) אִם פּוֹנֶה אַתָּה אַחֲרֵיהֶם אַתָּה עוֹשֶׂה אוֹתָן אֱלֹהוֹת, כְּלוֹמַר אִם אַתָּה מִתְעַסֵּק בְּעִנְיָנֶיהָ כְּלוֹמַר, לְהַרְהֵר אַחֲרֵי הַשִּׁגְעוֹנוֹת אֲשֶׁר יֹאמְרוּ הַמַּאֲמִינִים בָּהּ, שֶׁמַּזָּל פְּלוֹנִי אוֹ כּוֹכָב פְּלוֹנִי יַעֲשֶׂה פְּעֻלָּה כֵּן, וְכֵן בִּקְטֹרֶת פְּלוֹנִית אוֹ בַּעֲבוֹדָה פְּלוֹנִית, אוֹ תַּבִּיט תָּמִיד בַּצּוּרוֹת שֶׁעוֹשִׂין עוֹבְדֶיהָ כְּדֵי לָדַעַת אֵיכוּת עֲבוֹדָתָהּ, מִכָּל זֶה יִהְיֶה סִבָּה, שֶׁתִּהְיֶה נִפְתֶּה אַחֲרֶיהָ וְתַעַבְדֶהָ.
To not turn after the worship of idols — not in thought, not in speech and not in vision: To not turn after idolatry with thought or speech and not even only with sight; so that he not come from this to serve it, as it is stated (Leviticus 19:4), “You shall not turn to the idols.” And they, may their memory be blessed, said in Sifra, Kedoshim, Section 1:11, “If you turn after them, you make them gods”; meaning to say, if you involve yourself with their matters — meaning to ponder after the follies that those that believe in them say about it, that constellation x or star y does this action, and so [too,] incense x or service y; or you constantly observe the forms that their worshipers make in order to know the manner of its worship. All of this [can cause] you to be seduced after it and that you would worship it.
וּבְפֵרוּשׁ נֶאֱמַר שָׁם בַּסִּפְרָא, שֶׁאֲפִלּוּ הַהַבָּטָה לְבַד אֲסוּרָה, שֶׁאָמְרוּ שָׁם רַבִּי יְהוּדָה אוֹמֵר: אַל תִּפְנֶה לִרְאוֹתָן. וְהָעִנְיָן מִן הַטַּעַם שֶׁאָמַרְנוּ שֶׁהוּא סִבָּה לִרְאוֹת אוֹתָהּ וְלִטְעוֹת אַחֲרֶיהָ, וְכֵן כְּדֵי שֶׁלֹּא יְבַטֵּל חֵלֶק מֵהַזְּמַן וְיִתְעַסֵּק בְּאוֹתָם הַהֲבָלִים, וְהָאָדָם אֵינֶנּוּ נִבְרָא רַק לַעֲסֹק בַּעֲבוֹדַת בּוֹרְאוֹ, וְזֶהוּ שֶׁאָמְרוּ זִכְרוֹנָם לִבְרָכָה בְּשַׁבָּת פֶּרֶק שׁוֹאֵל אָדָם מֵחֲבֵרוֹ (קמט, א) וּדְיוֹקְנֵי עַצְמָהּ אֲפִלּוּ בַּחוֹל אָסוּר לְהִסְתַּכֵּל בָּהּ, מִשּׁוּם שֶׁנֶּאֱמַר אַל תִּפְנוּ אֶל הָאֱלִילִים. מַאי תַּלְמוּדָא? אָמַר רַבִּי יוֹחָנָן אַל תְּפַנּוּ אֵל מִדַּעְתְּכֶם.
And explicitly is it stated there in Sifra, Kedoshim, Section 1:10 that even observing alone is prohibited — as they said there, “Rabbi Yehudah says, ‘Do not turn, to see them.’” And the matter is from the reason that we said, which is that it causes [one] to see it and to stray after it. And also, so that he not waste a portion of [his] time and be involved in these vanities, whereas man is only created to be involved in the service of his Creator. And this is what they, may their memory be blessed, said in Shabbat 149a in the chapter [entitled] Shoel Adam Mechavero, “And [regarding] an image itself, even on a weekday it is prohibited to stare at it, because it is stated, ‘You shall not turn to the idols.’ What is the inference? Rabbi Yochanan said, ‘“Do not remove God (Al tefannu El” a play on the words of the verse) out of your minds.’”
וְנִכְפַּל לָאו זֶה, כְּלוֹמַר בְּאִסּוּר הַמַּחְשָׁבָה בַּעֲבוֹדָה זָרָה בְּמָקוֹם אַחֵר, שֶׁנֶּאֱמַר (דברים יא טז) הִשָּׁמְרוּ לָכֶם פֶּן יִפְתֶּה לְבַבְכֶם וְסַרְתֶּם וַעֲבַדְתֶּם וְגוֹ'. כְּלוֹמַר שֶׁאִם יַרְבֶּה לִבְּךָ לַחְשֹׁב בָּהּ, יִהְיֶה סִבָּה לִנְטוֹתְךָ מִן הַדֶּרֶךְ הַיְּשָׁרָה וּלְהִתְעַסֵּק בַּעֲבוֹדָתָהּ, וְעוֹד נֶאֱמַר בְּזֶה הָעִנְיָן (שם ד יט) וּפֶן תִּשָּׂא עֵינֶיךָ הַשָּׁמַיְמָה וְרָאִיתָ וְגוֹ'. שֶׁאֵין הָעִנְיָן שֶׁלֹּא יִשָּׂא הָאָדָם רֹאשׁוֹ וְיַבִּיט בַּשָּׁמַיִם, אֲבָל הַכַּוָּנָה בַּדָּבָר שֶׁלֹּא יַבִּיט בָּהֶם בְּעֵין הַלֵּב לָדַעַת כֹּחָן וְעִנְיָנָן, כְּדֵי לְעָבְדָן, וּכְמוֹ שֶׁנֶּאֱמַר בְּמָקוֹם אַחֵר (שם יב ל) וּפֶן תִּדְרֹשׁ לֵאלֹהֵיהֶם לֵאמֹר אֵיכָה יַעַבְדוּ הַגּוֹיִם הָאֵלֶּה אֶת אֱלֹהֵיהֶם וְאֶעֱשֶׂה כֵּן גַּם אָנִי וְגוֹ'. שֶׁיִּמְנָעֵנוּ הַכָּתוּב מִלִּשְׁאֹל עַל אֵיכוּת עֲבוֹדָתָהּ, לְפִי שֶׁכָּל זֶה הוּא סִבָּה לִטְעוֹת בָּהּ.
And this negative commandment — meaning, the prohibition of thought about idolatry — is repeated in another place, as it is stated (Deuteronomy 11:16), “Guard yourselves, lest your hearts be seduced and you serve, etc.” [This is] meaning to say that if your heart spends much time in thinking about it, it will be a cause to divert you from the straight path and to be involved in its service. And it is also stated about this matter (Deuteronomy 4:19), “And lest you lift your eyes to the heavens and see, etc.” As the content [of this verse] is not that a man not lift up his eyes to the sky and observe the heavens, but [rather] the intention of the thing is that he not observe them with his heart’s eye — to know their power and their makeup in order to serve them. And [it is] like it is stated in another place (Deuteronomy 12:30), “and lest you inquire of their gods, saying, ‘How do these nations serve their gods, and I will do so, me too, etc.’” The verse prevents us from asking about the manner of their worship, since all of this is a cause to err about it.
שֹׁרֶשׁ רִחוּק עֲבוֹדָה זָרָה יָדוּעַ לְכָל אָדָם.
The root of distancing ourselves from idolatry is well-known to every man.
דִּינֵי הַמִּצְוָה וּפְרָטֶיהָ, יִתְבָּאֲרוּ בְּהַרְבֵּה מְקוֹמוֹת בַּגְּמָרָא בְּפִזּוּר, שֶׁהִזְהִירוּנוּ בּוֹ זִכְרוֹנָם לִבְרָכָה (ברכות יב ב) שֶׁלֹּא לְהַרְהֵר בְּמַחְשֶׁבֶת עֲבוֹדָה זָרָה וְאָמְרוּ זִכְרוֹנָם לִבְרָכָה שֶׁלֹּא מַחְשֶׁבֶת עֲבוֹדָה זָרָה בִּלְבַד אֲסוּרָה, אֶלָּא כָּל מַחְשָׁבָה הַגּוֹרֶמֶת לוֹ לָאָדָם לַעֲקֹר דָּבָר מִן הַתּוֹרָה. וּבְפֵרוּשׁ הִזְהִיר הַכָּתוּב עַל זֶה דִּכְתִיב (במדבר טו לט) וְלֹא תָתֻרוּ אַחֲרֵי לְבַבְכֶם. וְאָמְרוּ זִכְרוֹנָם לִבְרָכָה (קידושין מ, א) שֶׁאֵין הַקָּדוֹשׁ בָּרוּךְ הוּא מְחַשֵּׁב לְיִשְׂרָאֵל מַחֲשֶׁבֶת עֲבֵרָה כְּמַעֲשֶׂה, חוּץ מִמַּחְשֶׁבֶת עֲבוֹדָה זָרָה, שֶׁהִיא נֶחְשֶׁבֶת לוֹ לָאָדָם כְּמַעֲשֵׂה [הלכות ע"א פ"ב].
The laws of the commandment and its details are elucidated in many scattered places in the Gemara, such that they, may their memory be blessed, warned us about it, not to ponder thoughts of idolatry (i.e. Berakhot 12b); and they, may their memory be blessed, said that it is not only the thought of idolatry that is forbidden, but rather any thought that causes a person to uproot something from the Torah. And Scripture prohibited this explicitly, as it is written (Numbers 15:39), “and you shall not stray after your hearts.” And they, may their memories be blessed, said (Kiddushin 40a) that for Israel, the Holy One, blessed be He, does not consider a thought of sin to be like the act — except for the thought of idolatry, which is considered for a man to be like the act. (See Mishneh Torah, Laws of Foreign Worship and Customs of the Nations 2.)
וְנוֹהֵג אִסּוּר זֶה בְּכָל מָקוֹם וּבְכָל זְמַן בִּזְכָרִים וּנְקֵבוֹת. וְהָעוֹבֵר עָלֶיהָ וּפָנָה אַחַר עֲבוֹדָה זָרָה בְּדֶרֶךְ שֶׁיְּהֵא עוֹשֶׂה בָּהּ מַעֲשֶׂה לוֹקֶה (עי' רמב"ם סנהדרין יט ד).
And this prohibition is practiced in every place and at all times by males and females. And one who transgresses it and turns after idolatry in a way that there be an act [involved] with it, is lashed. (See Mishneh Torah, The Sanhedrin and the Penalties within Their Jurisdiction 19:4.)