You arm's too short to box with the sender of the prophets
Nobody can box with (contest) God (the one who sent the prophets).
“Your arms are too short to box with God” is a reference to the first line of James Weldon Johnson’s “The Prodigal Son” “Young man— Young man— Your arm’s too short to box with God.”
However, given that this song is a tribute to Nas, this line might function more as an homage to this Nas line from “You Da Man”.
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