Hurt once and for all into silence
A long pain ending without a song to prove it
Who could stand beside you so close to Eden
When you glinted in every eye the held-high razor
Shivering every ram and son?
Now, silent looney-bin
Where the shadows live in the rafters like day-weary bats
Until the turning mind, a radar signal
Lures them to exaggerate mountain-size on the white stone wall
Your tiny limp
How can I leave you in such a house?
Are there no more saints and wizards
Probably a reference to Plato’s  allegory of the cave  about the happy state of unknowing (til you see the light of knowledge). The way Cohen uses the imagery here also reminds the reader of hallucinations and paranoia, induced by mental illness (A.M. Klein was suffering from mental illness).
To a Teacher