I think the "rap" style was an original creation of Bob Dylan.
His imagery is still unequalled.
"Darkness at the break of noon,
Shadows even the silver spoon,
The hand-made blade,
The child's ballon,
Eclipses both the sun and moon,
To understand you know too soon,
There is no sense in trying."
"Preachers preach of evil fates,
Teachers teach that knowlege waits,
Can lead to hundred dollar plates,
And goodness hides behind its gates,
But sometimes even the President of the United States,
Must have to stand naked."
"The poet is the priest of the invisible."