What defines monotheism?

Definition and Origin of the Term “Monotheism”

Monotheism is the belief in one, and only one, supreme God. The term comes from two Greek words: “monos,” meaning “single” or “alone,” and “theos,” meaning “god.” This concept of absolute oneness stands in stark contrast to polytheism, which teaches belief in multiple gods, and to henotheism, which acknowledges one supreme deity but still allows for lesser deities. Within the pages of Scripture, monotheism is not merely a philosophical idea but a core tenet of faith, worship, and life.

Monotheism in the Old Testament

The Old Testament consistently teaches the exclusivity of God. One of the most direct declarations is found in the Shema of Deuteronomy:

“‘Hear, O Israel: The LORD our God, the LORD is One.’” (Deuteronomy 6:4)

This passage is foundational to biblical teaching on God’s uniqueness. The first of the Ten Commandments emphasizes the need for singular devotion to this one God:

“‘I am the LORD your God, who brought you out of the land of Egypt, out of the house of slavery. You shall have no other gods before Me.’” (Exodus 20:2–3)

Throughout the Old Testament, prophets and poets echo the conviction that there is no other God. Isaiah underscored this by definitively proclaiming:

“‘I am the LORD, and there is no other; there is no God but Me.’” (Isaiah 45:5)

Archaeological findings, including ancient Hebrew inscriptions such as the ones discovered at Kuntillet Ajrud (8th century BC), demonstrate that the worship in Israel centered around Yahweh alone, setting them apart from surrounding polytheistic cultures.

Monotheism in the New Testament

The New Testament continues this monotheistic theme while revealing the triune nature of God. Readers find an unwavering commitment to “one God” (Ephesians 4:6), but also see the Father, Son (Jesus Christ), and Holy Spirit each fully expressed as God in Scripture, harmonizing together in what is often termed “Trinitarian monotheism.” The apostle James wrote:

“You believe that God is one. Good for you! Even the demons believe that—and shudder.” (James 2:19)

Monotheism remains central to the Christian faith, as the New Testament repeatedly affirms there is only one God (1 Corinthians 8:4–6). Yet Jesus is identified as divine (John 1:1–3, John 8:58, and elsewhere), and the Holy Spirit is likewise recognized as a person of the Godhead (Acts 5:3–4), demonstrating a depth of oneness within the tri-personal being of God.

Difference from Polytheism and Other Belief Systems

Monotheism fundamentally differs from polytheism, which posits the existence of multiple gods. Scripture consistently confronts and refutes polytheism, pointing out the futility of idol worship. While ancient Egyptian, Mesopotamian, and Canaanite religions had complex pantheons, Israel revealed a God who is transcendent, personal, and sovereign over all creation.

Additionally, monotheism contrasts with dualism—where two equal, opposing forces (often good and evil) coexist—and with pantheism—where the divine is equated with the universe itself. In biblical monotheism, God is the Creator distinct from His creation, yet personally involved in it (Genesis 1:1; Psalm 139:7–10).

Historical and Archaeological Corroboration

Numerous archaeological and textual discoveries affirm the consistent worship of one God in ancient Israel. The Dead Sea Scrolls (dating from roughly the third century BC to the first century AD) include texts of the Hebrew Bible that match with remarkable fidelity the monotheistic assertions found in Deuteronomy, Isaiah, and other Old Testament books. Such consistency indicates that the belief in one God was not a late development but rooted in the earliest recorded teachings of Israel.

Ancient witnesses such as Josephus (a first-century Jewish historian) reinforce that Israel’s religious life, rituals, and calendar centered on the worship of Yahweh as the one true God. This historical record, combined with the textual evidence from manuscripts, points to a remarkably stable monotheistic tradition.

Philosophical and Theological Implications

Biblical monotheism embeds a clear moral imperative: if God alone is Creator and sovereign, then humanity is called to respond with both worship and obedience. This exclusive devotion to God shapes ethical conduct, spiritual practice, and one’s entire worldview.

Philosophically, the belief in one uncreated, personal God provides a coherent framework for understanding the origin and purpose of life, moral values, and the meaning of existence. It also disarms the tension that arises in polytheistic systems where competing deities can claim allegiance and moral authority.

Practical Expressions of Monotheism

1. Worship and Prayer – Monotheism calls for worship directed exclusively to God. This is evident in the Psalms, which repeatedly invite people to exalt, thank, and praise God alone (Psalm 96:4–5).

2. Ethical Living – Since there is only one God who sets moral standards, monotheism demands an all-encompassing loyalty that affects personal behavior, social relationships, and justice (Micah 6:8).

3. Spiritual Identity – In both ancient Israel and the Christian congregation, identity is bound up with the understanding that believers belong to one God. Baptism, for instance, is administered “in the name of the Father, and of the Son, and of the Holy Spirit” (Matthew 28:19), reflecting a commitment to this singular divine identity.

Monotheism and the Uniqueness of Salvation

Scripture consistently presents God as the only source of salvation and deliverance. In the Old Testament, God alone rescues His people time and time again, exemplified by the Exodus narrative. In the New Testament, salvation through Jesus Christ underscores that there is no other path to eternal life:

“Salvation exists in no one else, for there is no other name under heaven given to men by which we must be saved.” (Acts 4:12)

The monotheistic claim that the one God has provided a single avenue for salvation through His Son underscores the essential nature of exclusivity—both in worship and redemption. From a biblical standpoint, multiple gods or multiple means of rescue are incompatible with the Lord’s own self-revelation.

Conclusion

Monotheism, as revealed in the Bible, is the unwavering conviction that there is one eternal, all-powerful, and personal God. From the Old Testament’s foundational creed, “The LORD is One,” to the New Testament’s seamless affirmation of the triune God, Scripture steadfastly teaches there is no other deity.

This monotheistic belief not only shapes theology but informs moral choices, worship practices, and cultural identity. Archaeological and historical records corroborate the biblical portrayal of a people defined by singular devotion to the one God, setting them apart from the polytheistic nations around them.

In sum, biblical monotheism is not a peripheral doctrine but the bedrock of faith, ethics, and ultimate reality. It underscores the uniqueness of God, unifies the message of Scripture, and directs the hearts of believers to a single, sovereign, and loving Divine Being who invites all to know Him.