" A proper interpretation of the epistles requires the recognition that it addresses 3 distinct groups of Jews: 1) believers: 2) unbelievers who were intellectually convinced of the gospel; and 3) unbelievers who were attracted by the gospel and the person of Christ but who had reached no final conviction about Him. Failure to acknowledge these groups leads to interpretations inconsistent with the rest of scripture."
Example: Hebrews
"The primary group addressed were Hebrew Christians who suffered rejection and persecution by fellow Jews (10:36-34), although none as yet had been martyred (12:4). The letter was written to give them encouragement and confidence in Christ, their Messiah and High-priest. They were an immature group of believers who were tempted to hold on to the symbolic and spiritually powerless rituals and traditions of Judaism.
The second group addressed were Jewish unbelievers who were convinced of the basic truths of the gospel but who had not placed their faith in Jesus Christ as their own Savior and Lord. They were intellectually persuaded but spiritually uncommitted. These unbelievers are addressed in such passages as 2:1-3; 6:4-6; 10:26-29; and 12:15-17.
The third group addressed were Jewish unbelievers who were not convinced of the gospel's truth but had had some exposure to it. Chapter 9 is largely devoted to them ( see especially vv. 11,14,15,27,28 )."