It was considered a threat because the Church considered having the knowledge of the Bible as a privilege reserved for the clergy. They felt it would reduce their status among general public if they were translated into the language of the common man. Also they feared that heretical teachings or misinterpretations occurring while transcribing.
The three-fifths compromise stated that an enslaved African American would count as three-fifths of a person when determining how many representatives each state would have by population.
