To many, Hebrews seems to a mysterious book filled with Old Testament references and expositions on the atonement. However, tThe author refers to it as a "word of exhortation" (13:22). It has a practical purpose with a shepherd's concern for a weary flock.The readers' difficulties included being ostracized, marginalized, persecuted, having their property confiscated, and things of this nature. Judaism was a legal religion protected under Roman law. For a time, Christianity was seen as a sect of Judaism and was therefore considered a legal religion. However, Jewish leaders made it clear that Christianity was not a sect, but a departure from Judaism, which gave Christianity the status of being an illegal religion. Various rumors against Christians of cannibalism, family disloyalty, treason, orgies, and things of this nature gave rise to the increased persecution Christians faced. Like Jews, Christians did not participate in much of public life due to the connections with pagan religion. Unlike Jews, they had no social network that would support them as outcasts. Jews had the synagogue, trade unions, Jewish markets, Jewish communities, etc. However, Christians converted from Judaism were driven from the synagogue, family, and all other social support they had in their life. The same could be said for many Christians converted from among the Gentiles. They had no temples, no official place of worship, no official center, and therefore often met in each other's homes to worship and fellowship. They were truly exiles in their own communities. Many were beaten down, weary, and exhausted due to the persecution they faced. Many were burned out due to the hardships they faced in their daily life. Apparently the persecution had increased, but they had not yet been murdered as a result of persecution (12:4). Their confession of faith in Christ was not as passionate as it once was. Some were meeting less and less with their Christian brethren. Some were barely doing anything that could identify them as Christian. Some were beginning to long for the earlier days when their families, communities, and former ways of life seemed so much easier. Some were in danger of returning to their former way of life, especially those converted from Judaism. This is the situation to which the book of Hebrews is addressed.
The author of Hebrews could have jumped straight into exhortation. However, his statement in 4:12 reveals that the word of God is what lays our innermost thoughts and intentions bare to God. Since the word of God is living and active, he engages in extensive exposition on the identity and work of Christ as the basis of his exhortation. This timeless teaching is the foundation for all doctrine and theological reflection in any time and any place. It helps the readers to ground themselves in unchangeable truth, which is found in the one whose years do not come to an end and who does not change. He tells his readers to consider Jesus (3:1; 12:3). In other words, the foundation and ground of Christian exhortation is the unchangeable, faithful Christ. Without this grounding, Christian teaching can become relativistic and subject to culture and "pop-theology" with little truth, little power, and little strength.
So, there are two parts to Christian encouragement. There is the identity and work of Christ, and there is the practical implications and application of it.