This appears to be clearly indicated in 1 Corinthians .The principle stated in 2 Corinthians -18 would seem to apply to marriage as well, and some might see it as applying to dating.Taking a census under such conditions would have been self-defeating. The last part of chapter 9 gives a prophecy about His coming and verse 27 mentions a “week” of His confirming the covenant, but that in the middle of the week He would bring an end to sacrifice and offerings.So from that passage of Scripture we can at least know one season when He was born—the winter. The book of Hebrews explains how His sacrifice ended the need for the Old Testament sacrificial system (chapters 8, 9 and 10).
One could certainly ask, “If a Christian cannot marry an unbeliever, why would they ever date one? I think one can have a friendship relationship with an unbeliever of the opposite sex, without entering into a dating relationship.Also, Jesus’ parents came to Bethlehem to register in a Roman census (Luke 2:1-4).The Romans would have known better than to have taken such a census in the dead of winter, when temperatures often dropped below freezing and roads were in poor condition for traveling.A “week” in prophecy can stand for seven years, a day for a year (Numbers ).We therefore conclude that His ministry lasted 3 ½ years, with the other 3 ½ years to be completed at some other time.