Do Jews, Muslims, and Christians worship the same God?

The simple answer is no. Jews and Muslims worship the same God but according to Torah and Jewish teachings Christians (Trinitarians) are idol worshipers.

Judaism teaches: Hear, O Israel: the Eternal One our God, the Eternal One is one. (Shema Yisrael: Adonai Elohainu, Adonai Echad) (Deuteronomy 6:4)

Islam teaches: There is no god but God. (lā ʾilāha ʾillā-llāh) (Shahada – first part)

Trinitarian Christianity teaches: For there are three that bear witness in heaven: the Father, the Word, and the Holy Spirit; and these three are one. (ὅτι τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῷ οὐρανῷ, ὁ πατὴρ, ὁ λόγος, καὶ τὸ ἅγιον πνεῦμα καὶ οὗτοι οἱ τρεῖς ἕν εἰσιν) (1 John 5:7)

As can easily be seen, Judaism and Islam teach the belief in ONE God whereas Trinitarian Christianity teaches the belief in THREE gods. Even one of the Names of God in the Tanakh – Eloh – is exactly the same Name as the God of the Quran – Allah.

“The closeness of Islam and Judaism was always understood by Biblical Scholars up until recent years. The close relationship between Jews, the ten lost tribes, the Arabs and Rachabites was all assumed. With the advent of German revisionists, Wellhausen and Büchler, and others, this all changed. They introduced ideas that Islam started with Moon or rock worship, or a falling asteroid. Devout Jews know that this is not true.

It is a fact of Jewish Law that we believe that Muslims are perfect monotheists. They worship the same God that we do.” (http://www.thesanhedrin.org/en/index.php/Hachrazah_5769_Kislev_15b)

“With regard to any gentile who does not serve false deities, e.g., the Arabs: It is forbidden to drink his wine, but it is permitted to benefit from it. Christians, by contrast, are idolaters. It is forbidden to benefit from their wine.” (Maimonides Ma’achalot Assurot 11:7)

I as a former Christian was an idol worshiper but since I have embraced Torah and Judaism I have come to worship the One True God – the God of Abraham Isaac, and Jacob.