Dear The Little,
The Mishna ends somwhere in the fifth perek. You are quoting one of the additions. This is prominently sourced. This particular teaching is considered to predate the Mishna. While it is a valid qoute, it is aggadah and does not obligate anyone.
He should not interrupt his studies. Rashi Kiddushin & Rambam Hilchos Talmud Torah