Turning 30

from the age of thirty years up to the age of fifty, all who are subject to service, to perform tasks for the Tent of Meeting.

He used to say: At five years of age the study of Scripture; At ten the study of Mishnah; At thirteen subject to the commandments; At fifteen the study of Talmud; At eighteen the bridal canopy; At twenty for pursuit [of livelihood]; At thirty the peak of strength; At forty wisdom; At fifty able to give counsel; At sixty old age; At seventy fullness of years; At eighty the age of “strength”; At ninety a bent body; At one hundred, as good as dead and gone completely out of the world.

"Thirty [is the age] for [full] strength": As the Levites would put up and take down the Tabernacle and load the carts and carry on their shoulders from [the age] of thirty and above.

The baraita notes that one verse states: “From twenty-five years old and upward” (Numbers 8:24), and one verse states: “From thirty years old and upward” (Numbers 4:47). It is impossible to say thirty, as twenty-five is already stated, and it is impossible to say twenty-five, as thirty is already stated. How can these verses be reconciled? Twenty-five years old is the time for apprenticeship and thirty for service. From here it is derived that a student who did not see a positive indication in his studies after five years will no longer see a productive result from those studies...

The Sages taught in a baraita: A priest, from the time he reaches puberty and grows two pubic hairs until he ages, is fit for Temple service, and blemishes disqualify him. A Levite from the age of thirty until the age of fifty is fit for Temple service, and the passage of years disqualifies him.

Joseph was thirty years old when he entered the service of Pharaoh king of Egypt.—Leaving Pharaoh’s presence, Joseph traveled through all the land of Egypt.

David was thirty years old when he became king, and he reigned forty years.