The author of Hebrews writes to believers to encourage them to focus on Christ because Christ is the apex of God’s revelation to humanity (Hebrews 1:1–3). The writer includes many calls to action, including this in Hebrews 3:13: “Exhort one another daily, while it is called ‘Today,’ lest any of you be hardened through the deceitfulness of sin” (NKJV).
Each call to action in the book of Hebrews is grounded on two ideas: the Hebrew Scriptures (the Old Testament) point to Christ (Messiah), and Christ is superior to everything prior that portrayed Him. Consequently, those who desire to rightly handle and apply the Scriptures need to focus on Christ. The writer of the letter to the Hebrews refers to the Hebrew Scriptures more than any other New Testament book (with around 15 percent of its content being quoted from the Old Testament). The writer explains that we must pay close attention to the message we have heard (and read) lest we drift away from it (Hebrews 2:1).
After explaining that Jesus is superior to the angels (Hebrews 2:5–16), that He is a faithful high priest (Hebrews 2:17—3:5), and that He is superior to Moses (Hebrews 3:6–11), the writer cautions readers to be alert (Hebrews 3:12). We need to cautiously avoid unbelief and turning away from the God who gave us life (Hebrews 3:12). Instead, day after day, we ought to exhort one another while it is still called “today” (Hebrews 3:13). That is, we need to be constantly encouraging and exhorting one another so that none of us will be hardened by the deceitfulness of sin.
The writer of Hebrews reminds readers of their current position in Christ. We are the house of God, if indeed we have the confidence and hope of Him to the end (and we do, according to Hebrews 3:6). We also have become partakers of Christ, if indeed we have the beginning or basis of the confidence held fast to the end (again, we do, Hebrews 3:13). If we have these things because of what the Christ has done for us, then we “must pay the most careful attention to what we have heard” (Hebrews 2:1). We ought to be exhorting one another right now, while it is still called “today” (Hebrews 3:13).
The writer adds that those who have believed will enter the rest promised to those who believe (Hebrews 4:3). While that promise is firm, believers should make sure that no one will even seem to come short of receiving that rest (Hebrews 4:1). In other words, God’s promise is certain, yet we should not take it for granted and ignore what He has told us.
The constant warnings in Hebrews are to believers who ought to walk like they have been saved by Christ—because they have. In order to help each other, we are supposed to exhort one another while it is still called “today.” As the writer says later in the letter, we ought to consider how to encourage one another to love and good deeds (Hebrews 10:24).