And if those days had not been shortened appears as an active construction in the Marcan parallel: “And if the Lord had not shortened the days” (13.20). For Mark “the Lord” is clearly a reference to God the Father rather than to Jesus. But Matthew probably realized how easily Mark’s account could be misunderstood, and so it was a simple matter for him to shift to the passive. For Matthew’s readers with their Jewish heritage, the understood agent of the passive verb would have been God: “But God has already reduced the number of those days.”
Days … shortened may imply for some readers the cutting short of the length of each day. Good News Translation‘s “reduced the number of days” resolves the problem. By shifting from days to “time,” New English Bible (“If that time of troubles were not cut short”) and New Jerusalem Bible (“And if that time had not been shortened”) suggest alternative possibilities of resolving the ambiguity. Die Bibel im heutigen Deutsch is effective: “If God had not cut short the time of terror.”
The sequence of verb tenses in this verse is problematic: if those days had not been shortened (a past tense) is followed by those days will be shortened (a future tense). In other words, the first half of the verse presupposes that what is announced in the second half has already taken place. Mark (13.20) uses the past tense in both halves of the saying. Perhaps what Matthew intends may be stated “If God had not already decided to cut short the number of days, then no one would survive. But God will cut short….”
The elect is translated “his chosen people” by Good News Translation (New English Bible “God’s chosen,” Barclay “God’s chosen ones,” Phillips “God’s people”). The terminology is once again drawn from Jewish apocalyptic sources but here applied to the Christian community. Terrible suffering will be experienced in those times, but God’s grace will see his people safely through. Possible renderings of the verse are “If God had not decided to reduce the number of days of the suffering, no one would be able to survive. But for the sake of his chosen people, he will cut this period short” and “That period of suffering will be so terrible that no one would be able to survive unless God decided to shorten it. But for the sake of his chosen people, God will reduce the number of days of the suffering.”
Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .