Definition and Distinction:
Favor and grace are closely related concepts in the Bible, often used interchangeably, yet they carry distinct nuances. Favor generally refers to the approval, support, or preference of God or man, while grace is the unmerited favor of God towards humanity. Both terms underscore the benevolent disposition of God towards His creation.

Old Testament Context:
In the Old Testament, the Hebrew word for favor is "chen," which is often translated as grace. Favor is depicted as a divine blessing that results in prosperity, protection, and success. For instance, Noah found favor in the eyes of the LORD, which led to his preservation during the flood (Genesis 6:8). Similarly, Joseph found favor in the sight of Potiphar, leading to his rise in authority (Genesis 39:4).

Grace, while not as explicitly mentioned in the Old Testament, is evident in God's dealings with Israel. Despite their repeated disobedience, God’s covenantal love and mercy are manifestations of His grace. The sacrificial system itself is a testament to God’s grace, providing a means for atonement and reconciliation.

New Testament Context:
In the New Testament, the Greek word for grace is "charis," which is central to the message of the Gospel. Grace is the foundation of salvation, as articulated in Ephesians 2:8-9 : "For it is by grace you have been saved through faith, and this not from yourselves; it is the gift of God, not by works, so that no one can boast." This grace is made manifest through Jesus Christ, who embodies the fullness of God's grace and truth (John 1:14).

Favor in the New Testament often refers to the goodwill and kindness of God that results in spiritual blessings. Mary, the mother of Jesus, is described as having found favor with God (Luke 1:30), highlighting her role in the divine plan of salvation.

Theological Significance:
Theologically, grace is foundational to the Christian understanding of salvation. It emphasizes that salvation is a gift from God, not earned by human effort but received through faith. This grace is transformative, leading to sanctification and a life that reflects the character of Christ.

Favor, while also a gift, often pertains to specific blessings or opportunities granted by God. It can be seen in the lives of biblical figures who, through their faithfulness, experienced God's favor in unique ways. However, favor is not always indicative of material prosperity; it can also involve enduring trials with God's presence and strength.

Practical Implications:
Believers are encouraged to seek God's favor and live in His grace. This involves a life of humility, obedience, and faith. James 4:6 reminds us, "But He gives us more grace. This is why it says: 'God opposes the proud, but gives grace to the humble.'" Christians are called to extend grace to others, reflecting the grace they have received from God.

In prayer, believers often seek God's favor for guidance, provision, and protection. The Aaronic blessing in Numbers 6:24-26 is a prayer for God's favor: "The LORD bless you and keep you; the LORD make His face shine upon you and be gracious to you; the LORD lift up His countenance upon you and give you peace."

Conclusion:
Favor and grace are integral to understanding God's relationship with humanity. They reveal His lovingkindness and the means by which He draws people into a covenant relationship with Himself. Through Jesus Christ, the ultimate expression of God's grace, believers are invited to live in the fullness of His favor and grace.