Abstract
One of the objectives of the Holy Qur'an is to recognize and know God. To this end, it refers to divine attributes in various instances. However, due to the focus of interpreters on achieving Qur'anic knowledge and uncovering the divine intent of the verses, the semantics of divine attributes have received less attention. This neglect has sometimes led to overlooking the Qur'an's goal of understanding divine attributes, and in other cases, it has resulted in misunderstandings in comprehending these attributes. This research employs a descriptive-analytical method to comparably examine two of the divine attributes in the Qur'an that are central to proving God's oneness. The findings indicate that the term "أحد" (Aḥad) signifies the simplicity of the essence of the Almighty, and God is free from any components and inward multiplicity. The term "واحد" (Wāḥid), on the other hand, has a broader semantic scope compared to "أحد" and conveys the meaning of negating multiplicity and external plurality regarding God. Through the comparison of these two terms, it becomes clear that both "أحد" and "واحد" are indeed necessary and complementary in describing God's uniqueness and oneness; for by negating inward multiplicity and affirming the simplicity of God,

Introduction

Tawḥīd is the first and most important principle of the Islamic creed, understood as the affirmation of God’s oneness. This principle is the common foundation among all divine religions, and its affirmation was the goal of all the prophets. Although the exact term tawḥīd does not appear in the Qur’an, many verses express and demonstrate this principle using various phrases.
Notably, the description of God’s uniqueness and unity in the Qur’anic verses is most often rendered by the term Wāḥid and, in some cases, by the term Ahad. Since these two words share a common root but differ in form, and given the premise that the Qur’an is the divine Word whose words and expressions are arranged with divine wisdom, the question arises: what semantic difference exists between the terms Wāḥid and Ahad, and how do they each indicate God’s oneness?
Scholars have outlined different kinds and aspects of tawḥīd and its manifestations, but among these classifications, the categories based on Wāḥid and Ahad have received comparatively little attention. This is despite the fact that both terms are considered and distinguished in the Qur’anic verses and in the narrations of the Ahl al-Bayt (peace be upon them), where differences have been noted.
The aim of this study is a comparative examination of the meanings of the terms Ahad and Wāḥid from the perspective of Qur’anic verses, so that by comparing their semantic fields, more precise concepts can be provided. Concretely, this research first investigates the meaning of Ahad in the Qur’an and in narrations, then explores the concept of Wāḥid, and finally analyzes and compares the similarities and differences in meaning between the two terms.
This study aims to answer the following questions:

What is the meaning of the attribute Ahad(أحد) when applied to the Exalted God?
What is the meaning of the attribute Wāḥid(واحد) in reference to God, given its frequent occurrences in the Qur’an?
What are the conceptual differences and points of comparison between these two attributes, and what conclusions regarding the knowledge of divine attributes can be drawn from considering them together in light of Qur’anic verses?


Literature Review

Scholarly background on divine attributes: Researchers in the field of Qur’anic studies have produced a limited number of works on the divine attributes. Notable examples include:

Muhammad-Reza Kashfi, who examined the semantics of divine attributes from the perspective of Allameh Tabataba’i, explained Allameh’s view based on the Transcendent Theosophy (Hekmat-e Motta’aliya).
Amir Khasas, in The Semantics of Divine Attributes from the Viewpoints of Ibn Maimun and Qadi Sa‘id Qummi, compared the two scholars and concluded that Ibn Maimun’s approach to the divine attributes is negational (apophatic), whereas Qadi Sa‘id Qummi’s is affirmational (cataphatic).
Mohammad Zabihi and Azam Iraji-Nia, in their study Ontological Examination of Divine Attributes from the Viewpoint of Ibn Sina with a Critique of Mulla Sadra, while acknowledging Ibn Sina’s precise exposition of divine attributes, criticize Mulla Sadra’s view on the supposed synonymy (convergence) of the attributes.
Hasan Abbasi Hossein-Abadi, in The Ontological Turn toward Divine Attributes in the Theological Thought of Allameh Hilli, explores the relationship between Divine Essence and attributes and explicates Allameh Hilli’s method of integrating theological, philosophical, and hadith-based approaches to prove God’s Essence.
Hossein Alavi-Mehr and Mohammad-Reza Haghighat have treated the semantics of “Ahad” in Sūrat al-Tawḥīdin a study that analyzes the meaning of Ahad in that sūrah exclusively on the basis of narrations (riwāyāt), without comparing it to Wāḥid.

Assessment of the literature: Scholarly background on divine attributes: Research on Qur’anic divine attributes is limited and largely ontological; semantic studies are fewer and often broader. Focused analyses of a single attribute across Qur’anic occurrences are rare. Studies of Ahad typically treat it in isolation (e.g., Sūrat al-Tawḥīd) and rely mainly on narrations without comparing it to Wāḥid.
Contribution and aim: This study fills that gap by semantically analyzing Ahad and Wāḥid as divine attributes in the Qur’an and conducting a comparative assessment that incorporates Shīʿī and Sunnī exegetical views.
Review structure:

Semantics of Ahad(lexicographers; commentators)
Semantics of Wāḥid(lexicographers; commentators)
Comparative study: commonalities and differences (semantics, usage, Qur’anic application)


Methodology

This study was conducted using a descriptive-analytical approach and a comparative method. The procedure was as follows:

The term Ahadwas first examined in early and later lexical sources. Thereafter, its concept was studied in light of the Qur’anic verses in which this term is employed as one of God’s attributes. Exegetical opinions of commentators from both the Shīʿī and Sunnī traditions were collected and analyzed in order to elucidate their meaning.
The same procedure was followed for the term Wāḥid: initially, its occurrences and senses were surveyed in classical and post-classical lexical sources; subsequently, its Qur’anic usages were explicated, and exegetical views regarding its meaning were analyzed.

In the final section, the meanings of the two terms in their respective usages as Ahad and Wāḥid were compared. The comparative study identified points of convergence and divergence in their sense, usage, and Qur’anic employment

Conclusion

After examining the two words Uhud and Wahid and comparing them, we reached the following results:
1- The word Uhud is not used in the singular form in a sentence and must be used in a numerical combination such as Uhud-e-Ash'ar, or an adverb such as Uhud-kam, or an adjective such as Uhud-mankam. However, the word Wahid also comes in both singular and compound forms.
2- The word Uhud must be used in a negative context, in which case it gives the sentence a general meaning, but the word Wahid can be used in both negative and positive contexts.
3- If the word Uhud is a description of God Almighty, it cannot be pluralized in any way, but Wahid itself has the ability to be pluralized.
4- The word Uhud is not used to describe a word, for example, a man is not called Uhud, but Wahid can be used to describe any word, for example, a dirham of Wahid.
5- Both words are part of the divine attributes, with the difference that one indicates the negation of multiplicity within the essence and the absence of parts, while one indicates the negation of multiplicity outside the essence and the absence of partners.
6- Each of these two words is necessary and necessary for each other, in the sense that the necessity of the being simple is that it has no partners. In other words, when God is one, he can also be one. On the other hand, an indispensable being can be one who is also one in his essence