In class tomorrow, we will discuss the origins of the abolition movement, which actually date much farther back that William Lloyd Garrison. It was Garrison, however, that often earns credit for being a pioneer in the abolitionist crusade. It is even more curious that Garrison denounced slavery in 1831--the very same year as Nat Turner's insurrection.
Is it just a coincidence that one of the leaders of the abolition movement emerges at the same year that a revolution takes place, causing more southerners to staunchly defend slavery? Consider how social movements, even today, often stir significant reactions from opposition groups (i.e. gun control, gay marriage, etc.).