Those in the Armenian position who, believing that one can lose his salvation, believe Matt. 10:22 teaches that unless one endures to the end he forfeits his salvation. Similarly, those in the Reformed position who, holding to the perseverance of the saints (i.e., all true saints will persevere), believe this passage teaches that a failure to endure to the end proves one was never saved. Other passages of similar emphasis sometimes used by these two groups are Hebrews 4:14; John 15:6; and Matthew 24:13; Mark 13:13. But none of these verses cited proves their contentions. Either these passages deal with rewards are physical endurance till the return of Christ.
It is important to remember that the use of words like “save” and “salvation” must be understood in their context. “Saved” often does not mean saved from sin or saved in the sense of receiving eternal life. It may simply refer so some form of deliverance or survival.
As one considers Matthew 10:22, it is vital to bear in mind the context which is Messianic and in keeping with the Old Testament calendar of events. Stanley Toussaint in Behold the King writes:
According to the Hebrew Scriptures the Messiah, after He appeared, was to suffer, die, and be raised again (Daniel 9:26; Psalm 22; Isaiah 53:11; Psalm 16:10). Following the death and resurrection of the Christ there was to be a time of trouble (Daniel 9:26-27; Jeremiah 30:4-6). The Messiah was then to return to the earth to end this tribulation and to judge the world (Daniel 7:9-13, 16-26; 9:27; 12:1; Zechariah 14:1-5). Finally, the Messiah as King would establish His kingdom with Israel as the head nation (Daniel 7:11-27; 12:1-2; Isaiah 53:11-12; Zechariah 14:5-11, 20-21).
In view of Matthew 10:23, “before the Son of Man comes,” Christ is looking forward past the church age to the days of the Tribulation, the time of Jacob’s trouble, when the gospel will be carried throughout the entire world before Jesus Christ returns in power and glory to establish His kingdom on the earth (Matthew 24:14). In the similar context using similar words, Matthew 24:8-31 (especially 24:13), the future Great Tribulation and the Second Advent are in view. As there, it would seem clear that the “coming of the Son of man” is eschatological here also. In keeping with their expectations from the Old Testament, such would have been more readily understood by the disciples. The endurance, then, is physical survival. While many will be martyred, a few will make to the end. Those who endure through the awful events of the tribulation will be alive or delivered by Messiah when he returns to earth. This is not a reference to eternal salvation from sin, but rather the deliverance of survivors at the end of the tribulation as stated in Romans 11:26, where the Deliver will save the nation Israel from its persecutors. Many will not endure to the end in that they will be martyred for their faith as described in Revelation 7:9-17.