The Jews have yet to complete the 70th week of Daniel to reconcile themselves with God. We know that it will be done by recognizing Jesus as their savior. His ministry lasted for 3 1/2 years. Why isn’t that counted towards the 7 years of the 70th week leaving 3/1/2 years for the Great Tribulation?
First let’s clarify that the 70th Week of Daniel won’t begin when the Jews accept Jesus. It will begin when they renew their Old Covenant relationship with God. They won’t accept Jesus as the Messiah until near the end of the 70th week (Zechariah 12:10).
The opinion that only the second half of Daniel’s 70th week is left is popular in some circles but doesn’t conform to scripture. Daniel’s 70 weeks prophecy is found in Daniel 9:24-27. It divides the 70 weeks ( each “week” is seven years long) into three segments; 7 weeks, 62 weeks and 1 week. Daniel 9:26 tells us that after the 62 week segment, the anointed one (Messiah) would be cut off and will have nothing (or, but not for Himself) and the city and sanctuary (temple) would be destroyed. The Hebrew word translated “cut off” means to be cut down, eliminated, killed. It’s a prophecy of the crucifixion.
But Daniel 9:27 tells us after that there will still be one week left. Therefore none of the Messiah’s time on earth can be subtracted from the final segment. The clock stopped at His death with one week (seven years) left to go.