"구약" refers to the Old Testament, which is the first part of the Christian Bible and is also sacred in Judaism. It contains a collection of texts that include historical narratives, laws, poetry, and prophecies. The Old Testament is divided into several sections, such as the Torah, the Historical Books, the Wisdom Literature, and the Prophets. The Old Testament primarily focuses on the relationship between God and the Israelites, detailing their covenant, laws, and the journey of their people. Key figures include Moses, who led the Israelites out of Egypt, and David, a significant king. The texts are foundational for both Jewish and Christian beliefs.