Verse 11
5:11-6:20 CHRISTIAN GROWTH AND PERSEVERANCE
Warning to the unstable (5:11-6:8)
The writer would like to say more about Christ's priesthood, but he feels his readers will not understand. Instead of being mature Christians they are spiritual babes, in spite of having received so much instruction in the Scriptures that by now they should be teachers themselves (11-12). They have not made the effort to study and understand the Word, and therefore are not able to apply its teachings to life's problems. Like children who have to be fed on milk, they have no ability to decide for themselves, but can only follow the lead of others. Mature Christians, by contrast, are like adults who can eat any food. They have trained themselves to discern between what is good and what is not (13-14).
Many Jews were of the childish kind just described. They said they were Christians, but they had made no progress. They seem to have merely added the name of Christianity to their former Jewish beliefs. Christianity, like Judaism, includes belief in sin, repentance, faith, cleansing, resurrection and final judgment, but Christianity involves more than mere acceptance of certain truths. If people do not progress beyond these basic beliefs, their Christian profession may soon be in danger. When persecution makes it uncomfortable for them to be known as Christians, they might give in to the temptation to go back to Judaism without changing their beliefs (6:1-3).
Christianity is not another name for Judaism. It completely replaces it, because Christ's death on the cross has made Judaism dead and useless. If people have joined in the life of the church and tasted the blessings that come through Christ's death, then deliberately renounce Christ, nothing is left for them but judgment. They have disowned and shamed Christ by an action similar to that of the people who crucified him (4-6).
Just as all the earth receives rain, so all who meet in the church receive God's blessings. But as some soil later proves to be bad, so some in the church later prove to be without life. Those with true faith prove it by their perseverance (7-8).
Verses 9-20
Encouragement to sincere believers (6:9-20)
Although some who received this letter needed such solemn warnings, others had clearly shown by their changed lives that they were genuine Christians. The writer has no doubts about such people (9-10). He encourages them to keep up the good work. They are not to lose heart or become lazy, but persevere to the end (11-12).
Warnings of judgment need not unsettle the believers concerning their assurance of salvation. When God promises salvation he keeps his word. Moreover, he confirms his promise with his oath (or vow). Abraham's confidence in God gave him patient endurance so that he received what God promised (13-15). In legal affairs people swear oaths to confirm their statements. In his grace God does the same. He gives people double assurance of salvation by giving his promise and then adding his oath (16-18).
The security of believers is based on the work of Jesus Christ. That work is their guarantee that God will never cast them out. The Levitical high priest entered God's presence as the people's representative when he went through the curtain into the Most Holy Place. Jesus Christ, the great high priest, enters God's presence as the Christians' representative. More than that, he is their forerunner. He is the guarantee that one day they too will be permanently in God's presence (19-20).