Tim, What is the significance of the number 72?
After sending out the twelve to proclaim the kingdom of God and heal (Lk 9), Jesus sent out 70 or 72 “others” ahead of where he was going to be (Lk 10:1). (Note: older Bibles say 70 and newer ones favor the manuscript reading 72, as do I.) The missions of the two groups are clearly similar (Lk 10:4=22:35 ESV; Cf. Matt 10:13 with Luke 10:6; Matt 10:15 with Luke 10:12; Matt 10:16 with Luke 10:3). But their numbers are very similar, too. Both are multiples of twelve; 72 being six times twelve. The twelve, of course, is based off the 12 tribes of Israel which the 12 apostles will sit on 12 thrones over in the Millennium (Mt 19:28). But why six times twelve for the second group?
The answer may be found in a third group to be sent out on the very same gospel preaching mission in the end times, the 144,000 (Rev 7:1). Unlike previous groups, they will proclaim the gospel to every nation and language in the world (Mt 24:14=Rev 14:1,6-7). Also unlike other groups they will receive special protection (Rev 7:1=9:4) from the Antichrist who is martyring believers during their mission (Rev 13:7,15,16). Their number is also a multiple of 12 and also 72.
So we have three groups of one times twelve, then six times twelve, and then twelve times twelve (times 1000) respectively. I believe the significance of the number 72 is to link that second group with the twelve and the 144,000 and also to indicate how their mission is only partial. The 72 are just an intermediate fulfillment of the greater final end time mission of the 144,000 who will preach the â€œeverlasting gospelâ€ in the entire world, not just Israel’s land. Being half of twelve times twelve is fitting in this role. Unlike the 72 who covered Canaan, the 144,000 will have to cover the entire world or all 72 of the biblical 72 nations of Genesis 10 (Septuagint text. Masoretic text lists 70). If the 144,000 go out in pairs like the 72 did, then the 144,000 can marshal 1000 pairs of gospel witnesses per biblical nation on earth.
For more on the 144,000 see my book or The Four End Time Groups: Will You Be in the Safe Group?