Reference for Taanit 53:11

אמר לך רב חמא בר גוריא תנאי היא ואנא דאמרי כי האי תנא דאמר שמונה

An objection was raised against this: Moses instituted for Israel eight Mishmaroth, four from [the family of] Eleazar and four [from the family of] Ithamar; David and Samuel came and increased them to twenty-four, as it is said, Whom David and Samuel the seer did ordain in their set office!<span class="x" onmousemove="('comment',' Ibid. IX, 22.');">⁵</span> - This is what the passage means: From their institution by David and Samuel the Ramathite they were increased to twenty-four.

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