Judaism, Islam, and Christianity share a belief in:

Monotheism:
- All three religions believe in the existence of only one God.
- In Judaism, this belief is expressed through the concept of Yahweh, the one and only God.
- In Islam, the belief in monotheism is encapsulated in the statement of faith, known as the Shahada, which declares that there is no god but Allah.
- In Christianity, monotheism is emphasized through the belief in the Holy Trinity, where God is understood as one being in three distinct persons: the Father, the Son (Jesus Christ), and the Holy Spirit.

Ethical Conduct:
- Judaism, Islam, and Christianity all emphasize the importance of ethical conduct and moral behavior.
- They provide guidelines and commandments for believers to follow in order to lead a righteous life.
- In Judaism, ethical conduct is outlined in the Torah, which includes the Ten Commandments and other laws.
- In Islam, ethical conduct is delineated in the Quran, which provides guidance on various aspects of life, including social justice, honesty, and compassion.
- In Christianity, ethical conduct is emphasized through the teachings of Jesus Christ, as recorded in the New Testament, which promote love, forgiveness, and compassion towards others.

Additional Points:
- While these three religions share common beliefs, they also have distinct theological and doctrinal differences.
- Judaism does not recognize Jesus Christ as the Messiah, whereas Christianity views him as the Son of God and the Savior.
- Islam considers Muhammad as the last and final prophet, while Christianity does not recognize him as such.
- Christianity and Islam both believe in the concept of an afterlife, with Islam emphasizing the idea of Paradise and Hell, and Christianity focusing on Heaven and Hell.
- Judaism has a different perspective on the afterlife, with a greater emphasis on the present life and the idea of an eternal reward in the world to come.

Overall, Judaism, Islam, and Christianity share a belief in monotheism and ethical conduct, but differ in their beliefs about key figures and the afterlife.