“You are to count seven Shabbats of years, seven times seven years, that is, forty-nine years. Then, on the tenth day of the seventh month, on Yom-Kippur, you are to sound a blast on the shofar; you are to sound the shofar all through your land.“-Leviticus 25:8-9
The opening verses of Leviticus chapter 25 were to establish the Sabbath year principle.
In other words, every seventh year was to be a complete rest for the land.
The standard Bible term used to explain the time frame for the Jubilee is “7 Sabbaths of years” or “7 weeks of years” meaning 7 x 7=49 years.
After this, the Jubilee Year which is the 50th year is to begin.
Now notice that the start of this special 50th year is YOM KIPPUR (Day of Atonement).
This is the 10th day of TISHRI which according to the religious calendar would be the 7th month of the year.
This might seem a bit strange because it appears that the beginning of the 50th year is being delayed by 10 days.
In terms of our modern calendar, it would be like saying we’re going to count the start of the 50th year from January 10th.
The 1st day of TISHRI is the Jewish New Year or ROSH HASHANAH.
But since the Hebrew word for “Jubilee” is YOVEL and since YOVEL means “Ram’s horn” and since the “Ram’s horn” is identified with YOM KIPPUR, then it is reasoned that the Year of Jubilee begins on the 10th day of the month TISHRI, which as we all know is YOM KIPPUR.
Honestly, not all Jews agree with this but that is the reasoning behind why the Year of Jubilee begins when it does.