Sifri: It implies that they are only Chayav if they prophesied or predicted deliberately, but not if the Navi was an Oneis of if the Cholem Chalom erred.

Rashi: It means he said something that is removed from reality, that Hashem did not command him to say.

Oznayim la'Torah: It means that he is Chayav for speaking alone - even though neither he nor his listeners, actually served Avodah Zarah, since he spoke perversely against Hashem.

Rashi: To teach us that, even if that had been the only thing that Hashem did for us ¹ , it would be sufficient reason to sentence the false prophet to death.

Ibn Ezra: In order to stress the point.

Alshich: Because Egypt was a fixed place for Avadim Ivri'im - no Eved Ivri ever escaped from there.

Divrei David (based on Gitin 37b): To teach us that, if someone redeems an Eved Ivri in order for the Eved Ivri to serve him, he (the Eved Ivri) is obligated to serve his new master. ²

Oznayim la'Torah: because in case the Navi Sheker thinks that the fact that Yisrael went out of Egypt has nothing to do wth him, bearing in mind what the B'al Hagadah said 'In every generation a person should consider it as if he went out of Egypt', the Torah is reminding him that Hashem redeemed him - personally - from the house of bondage.

Sanhedrin, 90a: It implies that he has the Din of a Navi Sheker even if he tries to negate only part of the sin of Avodah Zarah - and not all of it.

Sanhedrin, 90a: "Laleches" refers to a Mitzvas Asei (of Avodah Zarah) and "bah", to a Mitzvas Asei. ¹

Rashi (in Menachos, 99b): It is a Mitzvah incumbent upon whoever meets someone who is Chayav Misah to bring him to Beis-Din - in order to eliminate Resha'im from Yisrael.

Chulin, 141a: It teaches us that if a murderer escapes from Beis-Din before the conclusion of his court-case, it is Mitzvah to return him. ¹

Sanhedrin, 89b: Sekilah - which we learn via a Gezeirah Shavah 'Hadachah' 'Hadachah' from Meisis - in Pasuk 11. ¹