school (position) hard to enter (get)
Enter through the narrow gate. For the gate to perdition is great, and the way is broad. And there are many who go in through it. ---
This page is auto-translated from /nishio/狭き門 using DeepL. If you looks something interesting but the auto-translated English is not good enough to understand it, feel free to let me know at @nishio_en. I'm very happy to spread my thought to non-Japanese readers.