There is one myth that has no foundation: it is a total myth that having 13 at the last supper was unlucky. Also the term 'last supper' does not occur at all in any reputable translation of the Bible. It was not the last time Jesus will keep that supper.
There is one myth that has no foundation: that having 13 at the last supper was unlucky. On investigation thirteen (13) is found to be a very special number. The cultural fear of 13 is superstition. Also the term 'last supper' does not occur in any reputable translation of the Bible at all. Jesus was keeping the feast of the Passover. And it will not be the last time he will do so.
At the feast in the upper room of the unnamed man was a 'picture' or image of the future order of the kingdom of God. There were 12 men who were selected by God to take the message of the gospel to the people of Israel. And at their head was another, the 13th, who called himself the 'son of man' (John 13:31). The feast is introduced by Jesus who says to the 12 others,
With desire I have desired to eat this passover with you before I suffer: For I say unto you, I will not any more eat of it, until it be fulfilled in the kingdom of God. (Luke 22:15-16)
Jesus said this picture, or image, of 13 people gathered would be repeated again when the Passover is fulfilled in the kingdom of God. However, for a long while they would not be able to keep it. But one day, a long time in the future, they would keep the feast again in the same way as they did then. Jesus then picks up the cup of wine, which is part of the passover meal, and gave thanks, and said,
Take this, and divide it among yourselves: For I say unto you, I will not drink of the fruit of the vine, until the kingdom of God shall come. (Luke 22:17-18)
The record of Matthew adds that Jesus' very last words regarding this wine before they went out to the mount of Olives are,
But I say unto you, I will not drink from now on of this fruit of the vine, until that day when I drink it new with you in my Father's kingdom. (Matt 26:29)
Therefore this gathering of 13 will be repeated. Luke adds that Jesus promised the 12 at this Passover that the gathering (of 13) at the table would be repeated. Jesus said,
That you may eat and drink at my table in my kingdom,
and sit on thrones judging the twelve tribes of Israel. (Luke 22:30)
Previously Jesus had promised these 12 men the 12 thrones of the tribes in the regeneration of the kingdom to Israel,
Verily I say unto you, That ye which have followed me, in the regeneration when the Son of man shall sit in the throne of his glory, you also shall sit upon twelve thrones, judging the twelve tribes of Israel. (Matthew 19:28)
We know that Jesus is to sit on the the throne of his father David (Luke 1:32). That is a total of 13 thrones ruling Israel. The number 13, being 1+12, is very special to God. So special that when Judas failed they elected another Matthias to take his place (Acts 1:15-26).
God might like 13
We know that thirteen is important to God. The pattern of 12 and 13 (12+1) is repeated in the months of a Jewish lunar/solar year. Most years there are 12 months but 7 out of every 19 years have 13 months to keep the lunar calendar aligned with the solar cycle. God also required for the annual Jewish feast of Tabernacles on the fifteenth day of the seventh month when they did no work for seven days that on the 1st day
And you shall offer a burnt offering, a sacrifice made by fire, of a sweet savour unto the LORD; thirteen young bullocks (Numbers 29:12-13)
To please God they offered 13 bullocks. Actually there were 13 tribes in Israel. The children of Joseph made two tribes of Ephraim and Manasseh who were both numbered in the 12 tribes. Levi was made the priestly tribe and was separated without an inheritance of land (Numbers 18:24, Deuteronomy 10:9). This pattern is the same: 1 + 12.
The planned for traitor
The pattern's similarity with the disciples does not end there. One tribe is described as like 'a serpent' and its religion betrays the true religion. Jacob says in prophecy of his son Dan,
Dan shall judge his people, as one of the tribes of Israel. Dan shall be a serpent by the way, an adder in the path, that bits the horse heels, so that his rider shall fall backward. (Genesis 49:16-17)
This was fulfilled by those who worshipped the calves set up in Dan (1 Kings 12:28-31). They were punished and so fell 'backward'.
They that swear by the sin of Samaria, and say, “Thy god, O Dan, lives; and, The manner of Beersheba lives”; even they shall fall, and never rise up again. (Amos 8:14)
Those in Dan failed, just as Judas did. For of Judas it is said,
Now this man purchased a field with the reward of iniquity; and falling headlong, he burst asunder in the midst (Acts 1:18).
Judas, like those who worshipped the god of Dan, fell and did not rise again. That one of the 12 should be a traitor does not make the 12 less important. God gave Dan an inheritance, even knowing that from Dan would come betrayal. Judas, though a betrayer preached the true gospel as had the other eleven, he merely failed at one important point. For that betrayal Judas lost his role personally, but the role was important and it was given to another.
Twelve plus 1 is not about luck
When there were only eleven another was added to make twelve, as twelve was the number selected for rule. It was said of Ishmael in blessing,
Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation. (Genesis 17:20)
By contrast the princes, or dukes, of Edom were only 11. For Israel to be a great nation it was to have 12 princes. From Jesus' promise to his apostles we know who these 12 will be. They will sit on 12 thrones.
Nowhere in the Bible is 13 bad. Thirteen is the number of cities Simeon inherited, the number of cities the Kohathites had in Benjamin, the number of cities the Gershonites had in Issachar, Naphtali and Manasseh, the number of the total of the cities of the children of Aaron. Solomon was 13 years building his house. And the length of the gate of the temple of Ezekiel is to be 13 cubits.
In this list the number is about cities. It's very neutral. So why is 13 considered unlucky or lucky?
It was not luck that Judas made 13, and the betrayal was not unlucky. The Bible says that reasonably early in the ministry Jesus said,
“Have not I chosen you twelve, and one of you is a devil (slanderer/ false accuser)?” (John 6:70)
This indicates Jesus actually chose someone who he knew all the time was to betray him. It wasn't chance! The betrayal was a deliberate action, not a chance outcome of events. This should not be considered an example for why 13 is unlucky. The people who think so don't know the Bible.
But the number 13 clearly was associated with pagan superstition.
Some afflicted by this superstition, called Triskaidekaphobia, call the '13th' floor the '14th', (not realising that labelling it differently makes it no less the 13th floor). In the same way the Code of Hammurabi, approx. 1780 BC, according to hearsay, omitted the thirteenth law. Another source indicated Persians also once believed they had to stay in their houses to avoid bad luck on the thirteenth day. Another source speaks of the Song of Ishtar, an ancient Babylonian epic poem with the thirteenth line containing the name of the Goddess of the Dead. Quite a few sources quoted a Norse myth which tells of 12 gods dining at Valhalla where a 13th uninvited guest, Loki, arrived, persuading the god of darkness to slay the god of happiness.
It could be suspected that ancient superstitions would be related to the pagan fears regarding their gods. They had no relationship with their gods, so they could never know why things went right or wrong. They could merely assume that a bad day or year was the result of not appeasing the god. They made gods of the sun and moon (there are 80 different moon deities listed by Wikipedia from pagan cultures world wide). The moon was often in ancient cultures a goddess, due to the female cycle. As there were approx. 12.41 lunar cycles per solar year, making a normal year 12 months, with some years of 13 months, it is logical that pagans might have worried about what a goddess might do in the coming of the 13th month.
The symbolism of 13
But let us ponder what the number 13 is really about. In 1015 Vladimir, the founder of Russia's greatness divided his empire into 13 principalities. The number of states that formed the original union of the United States was 13. The original flag had thirteen stars. In this case the first number of a great nation was 13. The great nation of Saudi Arabia is made up of 13 Emirates (Cp.Genesis 17:20). The number of loaves in a "baker's dozen" is 13. This came about by English law 1266–1267 (the 13th century) in the time of Henry III in one of the earliest English statutes (not repealed until 1863), which graduated the minimum weight of bread according to the price of wheat. By baking 13 loaves a baker could ensure they would not be prosecuted for selling underweight bread. It also happens that 13 loves fit better on a rectangular tray. In this way 13 is a number of the British nation, as by its this law it established government regulation of commercial trade. These are all examples where the number 13 is related to the governance of a nation.
Why should we fear to gather 13 to a table when, quite clearly, Jesus the great leader is happy to repeat the gathering? He said in effect, we will meet like this about a table again. Except Judas was be replaced by Matthias. And the table will not be hidden in an upper room.
Why should we fear to have 13 floors on a building when God is clearly quite happy with 13 in his building. God chose 13 cubits (the measure of a forearm) as a measure of the entrance of his future temple (Ezekiel 40:11). This is amazing in symbol, as it is through the work of the Apostles (their arms and hands) that we can know and enter our hope. And there were 13 Apostles! The 12 plus Paul. Paul was called last. Paul says,
And last of all he (Jesus) was seen of me also, as of one born out of due time. For I am the least of the apostles, that am not fit to be called an apostle, because I persecuted the church of God. (1Corinthians 15:8-9)
In any case the number 13 in the Bible is neither unlucky nor lucky, and if it symbolises anything at all, it symbolises the order of the sun and moon, and the order of a great nation. The 13 men at table in the upper room gathered to keep the Passover, were the government in waiting of the still future regenerated Israelite Kingdom of God.
In that kingdom 13 will be the number of the thrones of the greatest nation ever on earth. A nation with thrones for each of the twelve apostles, plus the throne of David, for Jesus, a king greater than Solomon. A king of kings.
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