בראשית, פרק א׳, פסוק ה׳

The creation of time and the establishment of its order mark the first practical stage in shaping the universe. After bringing light and darkness into existence, God grants them distinct roles, meanings, and boundaries, thereby forming the first chronological cycle in history. Assigning names to these elements goes beyond simple classification; it is an expression of absolute dominion, defining their very essence and purpose [רשב״ם, שד״ל]. God appoints the light to govern the daytime, establishing its limits much like a king who appoints ministers and delegates authority [תורה תמימה, רש״ר הירש]. The concept of day refers specifically to the period when light actively functions, while night is the designated time for darkness to rule [הכתב והקבלה, אברבנאל]. Darkness is not merely the absence of light, but a profound, substantial creation in its own right, given its own boundary and function by God [העמק דבר]. However, while God explicitly associates His name with the light, He does not directly attach His name to the darkness. The Creator distances His direct presence from darkness and adversity, reserving that explicit association solely for the good [חזקוני, ברכת אשר, בית הלוי].

The transition between these states of light and darkness introduces the concepts of evening and morning. The essence of evening is rooted in the idea of mixture and blurring, capturing the moment when fading light causes shapes and sights to blend together, making them indistinguishable to the human eye [אבן עזרא, רמב״ן, רד״ק, שד״ל, רש״ר הירש]. Conversely, morning conveys distinction, clarity, and examination, as the rising light allows objects to be clearly distinguished from one another [אבן עזרא, רמב״ן, רד״ק, רש״ר הירש]. Others understand morning as the literal breaking forth of the light [שד״ל]. The sequence of evening preceding morning reflects the reality that darkness existed before light in the order of creation [שד״ל, אברבנאל]. This specific sequence permanently establishes the foundation of time in Judaism, dictating that a full day begins at night and concludes at the end of the following daytime [תורה תמימה, קאסוטו].

Since the sun and moon were not created until the fourth day, a natural question arises regarding how evening and morning functioned initially. The primary approach among commentators is that the primordial light actively fulfilled this role, shining and setting gradually. This created a twenty-four-hour cycle where light and darkness revolved around the earth, meaning that while it was morning in one location, it was evening on the opposite side [אבן עזרא, רמב״ן, הטור הארוך, העמק דבר, תורה תמימה]. Another perspective suggests that the light was created, immediately withdrew to establish the measure of night, and then rose once more to complete a full cycle [מלבי״ם, תולדות יצחק].

This initial cycle of creation is defined as a single, unified day rather than the first day of a sequence. Logically and conceptually, an entity cannot be categorized as first until a second exists; since no other days had yet been created, it is simply referred to as one [רמב״ן, רד״ק, קאסוטו]. Beyond logic, this formulation teaches a profound lesson about the absolute unity of God, emphasizing that He was entirely alone in His world before the angels were created on the following day [רש״י, הטור הארוך, אברבנאל]. Furthermore, this serves to refute dualistic beliefs that assign separate divine powers to light and darkness. It underscores that a single God created both of these opposing forces, and together they form the day of one God [כלי יקר]. Ultimately, the concept of unity here signifies a complete entity, teaching that the seamless joining of evening and morning creates a single, whole unit of time [שד״ל, אבן עזרא, ביאור שטיינזלץ]. This specific day remains entirely unique from the rest of creation, as it was the only time when absolute creation from nothingness occurred, whereas all subsequent days involved forming new entities from existing matter [נחלת יעקב].