Exodus 22:19

Whosoever sacrificeth to the idols of the Gentiles shall be slain with the sword, and his goods be destroyed; for ye shall worship only the Name of the Lord.

HE THAT SACRIFICETH ‘LO’ELOHIM YOCHARAM’ (SHALL BE UTTERLY DESTROYED). “Lo’elohim means to the idols, for since the word is voweled with a patach, and kamatz are in this sense alike, as both indicate the definite article — “those gods which in another place you have been forbidden to worship.” The word lo’elohim is voweled with a kamatz. it means those gods which in another place you have been warned not to worship.” This is Rashi’s language. Rabbi Abraham ibn Ezra commented that in accordance with the plain meaning of Scripture, this command is not directed to Israel, as they had already been warned in the second of the Ten Commandments against the worship of idols. Instead it was said to “the stranger” mentioned in the following verse, that he may live in our land only on condition that he should not sacrifice to his gods as he was wont to do. — But he [i.e., Ibn Ezra] openeth his mouth in vanity. For in the Ten Commandments He warned against idolatry by a prohibition, and here He explained the punishment and the law that we are to apply to he who transgresses that commandment, just as He did in the case of Thou shalt not murder; Thou shalt not commit adultery, for these are the ordinances which He set before them [with respect to these commandments]. Thus He is hereby declaring that one who sacrifices to idols is guilty of death, for the term yocharam means death by the court. Similarly we find, All ‘cheirem’ that may be ‘yocharam’ of men may not be ransomed; he shall surely be put to death. signifies death by the court. He uses the term yocharam [of the root cheirem — unlawful, anathema], because he who sacrifices to that which is anathema, deserves destruction, similar to that which is said in the verse, And thou shalt not bring an abomination into thy house, and be ‘cheirem’ (accursed) like unto it; thou shalt utterly detest it, and thou shalt utterly abhor it; for it is an accursed thing.
It is possible that the verse includes the slaughterer and the animal slaughtered, to tell us that they both go to cheirem (destruction), thus hinting that it is forbidden to derive any benefit from that which has been offered to the idols. It mentioned sacrificing, but the same law applies to bowing down before the idol, and to all other acts of worship performed in the Sanctuary, but other acts of worship — such as sweeping it, …

זבח לאלוהים, the vowel patach under the letter ל makes it clear that an alien deity is meant. If the meaning were a sacrifice to G’d, the vowel under the letter ל would be a tzeyreh

לאלוהים, to the ones concerning which I said in the Ten Commandments לא יהיה לך אלוהים אחרים, “you must not have any other deities.” (20,2)

זובח לאלוהים, to all the deities simultaneously. This is forbidden even though the worshipper includes Hashem in the address to which the sacrifice is tendered.

יחרם, the person will be executed and the offering itself is prohibited for any use whatsoever. Just as the false deities are to be banished totally, so those who believe in them. (compare Deuteronomy 7,26 )

לה' לבדו, excluding any possible partner.