Biblical Context:
Isaac, the son of Abraham and Sarah, is a patriarch in the biblical narrative, known for his role in the continuation of God's covenant with Abraham. The account of Isaac building an altar is found in Genesis 26, a chapter that highlights God's reaffirmation of His promises to Isaac and the patriarch's response in faith and worship.

Scriptural Reference:
The primary passage concerning Isaac building an altar is Genesis 26:23-25. The Berean Standard Bible states:

"From there Isaac went up to Beersheba, and that night the LORD appeared to him and said, 'I am the God of your father Abraham. Do not be afraid, for I am with you. I will bless you and multiply your descendants for the sake of My servant Abraham.' So Isaac built an altar there and called on the name of the LORD, and he pitched his tent there. His servants also dug a well."

Theological Significance:
Isaac's construction of an altar at Beersheba is a significant act of worship and obedience. It reflects his acknowledgment of God's presence and promises. The altar serves as a physical manifestation of Isaac's faith and his commitment to the covenant established with his father, Abraham. By building the altar, Isaac not only honors God but also establishes a place of worship and communion with the Divine.

Covenantal Continuity:
The act of building an altar is deeply rooted in the patriarchal tradition, as seen in the lives of Abraham and later Jacob. It signifies the continuity of God's covenantal relationship with the patriarchs. God's appearance to Isaac and the reiteration of the promises made to Abraham underscore the unbroken line of divine blessing and purpose. Isaac's response by building an altar is a testament to his role as a bearer of the covenant.

Symbolism and Worship:
The altar symbolizes a place of sacrifice, worship, and divine encounter. In the ancient Near Eastern context, altars were central to religious life, serving as sites where individuals could offer sacrifices and seek communion with their deity. For Isaac, the altar at Beersheba becomes a sacred space where he calls upon the name of the LORD, signifying his reliance on God's guidance and provision.

Isaac's Faith and Obedience:
Isaac's actions demonstrate his faith and obedience to God. Despite the challenges he faced, including disputes over wells with the Philistines, Isaac remains steadfast in his devotion. His decision to build an altar and call upon the LORD highlights his trust in God's promises and his willingness to follow in the footsteps of his father, Abraham.

Historical and Cultural Context:
In the patriarchal era, altars were often constructed at significant locations where God revealed Himself or where pivotal events occurred. Beersheba, where Isaac builds the altar, holds historical and spiritual importance as a place associated with God's covenantal promises. The act of digging a well alongside the altar further emphasizes the themes of provision and sustenance, both physically and spiritually.

Conclusion:
Isaac's building of an altar at Beersheba is a profound expression of his faith and commitment to God's covenant. It serves as a reminder of the enduring relationship between God and the patriarchs, highlighting themes of worship, obedience, and divine promise.