[Stanza 1]
My parents kept me from children who were rough
Who threw words like stones and wore torn clothes
Their thighs shown through rags. They ran in the street
And climbed cliffs and stripped by the country streams.
[Stanza 2]
I feared more than tigers their muscles like iron
Their jerking hands and their knees tight on my arms
I feared the salt coarse pointing of those boys
Who copied my lisp behind me on the road.
[Stanza 3]
They were lithe, they sprang out behind hedges
Like dogs to bark at my world. They threw mud
The boys perceive the speaker’s accent as alien and ‘posh’, whether the ‘lisp’ is real or a perception.  Whichever way, a lisp is a speech impediment; unmasculine and demeaning. But clearly their reaction, to stalk him, is threatening and insulting.