Among the many titles and descriptions we find for Jesus throughout the scriptures, perhaps none were so vivid to the mind of first-century Jewish Christians as those found in Hebrews 3:1 – the Apostle and High Priest of our confession. The Holy Spirit urges these Christians to contemplate, gaze upon Jesus in these roles. He wants them to focus their attention carefully and seriously, taking in all the significance for them of Jesus, compared to Moses (as persecuted Jewish Christians who were being tempted to return to worshipping “through” Moses instead of the Christ). Jesus is described both as “the” apostle (this is the only passage in the bible where this word is applied to Him) AND as the High Priest of all Christians (a contrast to the Jewish high priests who were still present in Jerusalem when this was written).
An apostle is a messenger, one who speaks with the authority of the one who sent him – in this case, there is an unmistakable comparison of the authority of Moses with that of Jesus (vs. 2 – both faithful, as lawgivers sent by God), and verses 3-6 emphasize that the authority of Jesus would necessarily exceed that of Moses as the authority of a son exceeds that of a servant. In other words, the “message” (law) delivered by Jesus should carry greater “weight” with these Jewish Christians than the one delivered by Moses!
Likewise, a priest is one who stands between man and God; by calling Jesus “the” High Priest of our confession, the inspired writer both reinforces to these Christians that they have accepted the gospel in the place of their previous faithfulness to the law of Moses, and that Jesus again “outranks” Moses, by serving in a way he never had – as the ultimate “go-between” to represent man in the presence of God. For these Jewish Christians, these facts emphasized the point that there could be no “going back” to Judaism in place of Christianity, because someone and something superior (Jesus and Christianity) had taken the place of Moses and the law.
The balance of Hebrews 3 presents two profoundly important facts about Christian faith. UNbelief leads one away from God (vs. 12), and disobedience and disbelief are the same thing (vv. 18-19). In verse 12 the Holy Spirit plainly contradicts the idea that a Christian cannot become lost once again – these Christians are described as “brethren” (an indicator of their relationship with Christ), but also warned about “departing” (withdrawing from, deserting) God. Unbelief leads to a attitudinal change in the condition of the heart (from good to “evil”), which causes loss of faith. Paul described this condition in 1 Timothy 4:2, when he described those who “depart from the faith” as having consciences that have been “seared” (lit. cauterized, burned beyond feeling).
In verses 18-19 the warning for these Jewish Christians is rooted in the example of the “slave” generation of ancient Israel, who – after seeing the mighty works of God to deliver them from bondage in Egypt – had refused to enter the promised land at Kadesh-Barnea (Numbers 13:31-14:4). Because they disobeyed the Lord’s instruction to “go in and conquer,” God had “sentenced” them to die in the wilderness (Numbers 14:23) rather than even see His promised land; and at Hebrews 3:19, the Holy Spirit makes the point that the root of their problem was their unbelief. In John 6:29, Jesus had made the point that believing HIM is the “work” God has prescribed for us, and in Hebrews 4:2 the Holy Spirit makes the application these Jewish Christians needed to see – that “obedience” (in their case, observing the form of a law) could provide no benefit if it was divorced from faith.