This page was last updated on 29 December, 2014.
The 13th month of Ezekiel
On the main page I wrote that a lunar month is about 29.54 days long and because there are no half days on a calendar some months were 29 days long, while others were 30 days long. That gives an average that’s quite close to 29.54. A similar problem exists with lunar months not fitting into a solar year.
A lunar month is about 29.5 days long. A solar year is about 365 days long.


That’s a 365
Ezek 1:1 Now it came to pass in the thirtieth year, in the fourth month, in the fifth day of the month, as I was among the captives by the river of Chebar, that the heavens were opened, and I saw visions of God.
Ezek 1:2 In the fifth day of the month, which was the fifth year of king Jehoiachin's captivity,
Ezek 3:15 Then I came to them of the captivity at Telabib, that dwelled by the river of Chebar, and I sat where they sat, and remained there astonished among them seven days.
11th day of the 4th month of the 5th year of king Jehoiachin's captivity.
Ezek 4:4 Lie you also on your left side, and lay the iniquity of the house of Israel on it: according to the number of the days that you shall lie on it you shall bear their iniquity.
Ezek 4:5 For I have laid on you the years of their iniquity, according to the number of the days, three hundred and ninety days: so shall you bear the iniquity of the house of Israel.
Ezekiel is ordered to lay on his left side for 390 days.
Ezek 4:6 And when you have accomplished them, lie again on your right side, and you shall bear the iniquity of the house of Judah forty days: I have appointed you each day for a year.
Ezekiel is ordered to lay on his right side for 40 days
390+40=430 days.
Ezek 8:1 And it came to pass in the sixth year, in the sixth month, in the fifth day of the month, as I sat in my house, and the elders of Judah sat before me, that the hand of the Lord GOD fell there on me.
Ezekiel is sitting, so his 430 days must be over. Time for some math :
Ezekiel received his commands on 11th day, 4th month, 5th year.
Ezekiel was sitting on the 5th day, 6th month, 6th year.
Solar year
Start: 11th day, 4th month, 5th year.
Add 1 year.
Result: 11th day, 4th month, 6th year.
Left: 430
Months left: 65/30.5*=2.13 months = 2 months and about 4 days.
Result: 15th day, 6th month, 6th year.
Ezekiel sits 5th day of 6th month.
Calculated end of 490 days: 15th day of 6th month.
Ezekiel was sitting 10 days early.
*=A solar month is 30.5 days on average. It was past February which is 28 or 29 days.
12 month lunar year
A lunar year is (29+30)/2x12=354 days.
Start: 11th day, 4th month, 5th year.
Add 1 year.
Result: 11th day, 4th month, 6th year.
Left: 430
Months left: 76/29.5=2.57 months = 2 months and about 17 days.
Result: 28th day, 6th month, 6th year.
Conclusion: Eze 8:1 tells us Ezekiel was sitting on the 5th day, but this calculation shows the 430 days end on the 28th day. So Ezekiel was sitting 23 days early.
Ezekiel sits 5th day of 6th month.
Calculated end of 490 days: 28th day of 6th month.
Ezekiel was sitting 23 days early.
13 month lunar year
An extra month simply means the end day is one month earlier but here is the full calculation anyway.
A leap lunar year is (29+30)/2x13=383 days.
Start: 11th day, 4th month, 5th year.
Add 1 year.
Result: 11th day, 4th month, 6th year.
Left: 430
Months left: 47/29.5=1.59 months = 1 months and about 17 days.
Result: 28th day, 5th month, 6th year.
Ezekiel sits 5th day of 6th month.
Calculated end of 490 days: 28th day of 5th month.
Ezekiel was sitting a week after his 430 days ended.
All the above calculations use rounded numbers so the exact results may vary a little. But most certainly not 10 days to make a solar calendar work. Please note that those 10 days likely are 11 or 12 days because Eze 4:9 shows Ezekiel first had to bake 390 days worth of bread, which would have taken 1 or 2 days. So the 430 days likely started on the 12th or 13th so the error is 11 or 12 days.
Anyway this article has proven from Scripture:
a] The solar calendar isn’t used in the Bible.
b] The 12 month only lunar calendar isn’t used in the Bible.
c] A lunar calendar with an occasional 13th month IS used in the Bible.
Conclusion: The 13th month, a leap month, is Scriptural.
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