Who was Cain's brother?

Cain's brother was Abel. They were the first two sons born to Adam and Eve after their expulsion from the Garden of Eden, as recorded in the book of Genesis. The narrative in Genesis chapter 4 describes their distinct vocations: Cain became a tiller of the ground, while Abel was a keeper of sheep. This occupational difference played a pivotal role in the tragic events that unfolded, specifically concerning their offerings to God. Cain brought an offering of the fruit of the ground, while Abel brought the best of the firstborn of his flock, along with their fat. God regarded Abel's offering with favor but did not regard Cain's, leading to Cain's deep resentment and jealousy.

The narrative of Cain and Abel is set in the earliest period of human history, immediately following the expulsion from the Garden of Eden. This period, often referred to as the antediluvian (pre-Flood) era, is characterized by a primitive agrarian and pastoral lifestyle. Archaeological evidence for specific sites related to these earliest biblical narratives is scarce due to their extreme antiquity and the geological event of the global flood, which reshaped the earth. However, the cultural context reflects an emerging agricultural society alongside nomadic herding, a common economic duality in the ancient Near East. The concept of offering sacrifices to deities was widespread in ancient cultures, signifying propitiation, thanksgiving, or covenantal affirmation. The account highlights foundational human themes such as sin, jealousy, fratricide, and divine justice and mercy, setting a precedent for understanding human moral failings and God's interaction with humanity from its nascent stages.

The narrative of Cain and Abel serves as a profound theological statement on the nature of sin, righteousness, and divine judgment. Abel's offering, made 'by faith' as Hebrews 11:4 attests, highlights the principle that true worship involves not merely the act of giving, but the attitude and heart behind it, coupled with a proper understanding of what is acceptable to God. Cain's failure to offer in faith, coupled with his subsequent jealousy and murderous rage, demonstrates the pervasive corruption of sin that entered humanity through Adam and Eve's transgression. God's dialogue with Cain before the murder, 'If you do well, will it not be lifted up? If you don’t do well, sin couches at the door. Its desire is for you, but you are to rule over it' (Genesis 4:7), underscores human responsibility for choosing righteousness over sin, even when sin's temptation is strong. The tragic outcome—the first human murder—reveals the destructive power of unaddressed envy and anger, leading to a curse and further separation from God's presence.