A wretched thing it were, to have our heart

A wretched thing it were, to have our heart
Like a thronged highway or a populous street,
Where every idle thought has leave to meet,
Pause, or pass on as in an open mart;
Or like some roadside pool, which no nice art
Has guarded that the cattle may not beat
And foul it with a multitude of feet,
Till of the heavens it can give back no part.
But keep thou thine a holy solitude,
For He who would walk there, would walk alone;
He who would drink there, must be first endued
With single right to call that stream his own;
Keep thou thine heart, close-fastened, unrevealed
A fenced garden and a fountain sealed.