The pope uses in the bull almost the same language as in his letter, Veritas ipsa to Cardinal Juan de Tavera, Archbishop of Toledo, sent less than a month earlier on May 2, 1537. Paul III unequivocally declares the indigenous peoples of the Americas to be rational beings with souls, denouncing any idea to the contrary as directly inspired by the "enemy of the human race" (Satan). He goes on to condemn their reduction to slavery in the strongest terms, declaring it null and void for as well as for any people known or that could be discovered in the future, entitles their right to liberty and property, and concludes with a call for their evangelization.
The bull had a strong impact on the Valladolid debate, and its principles eventually became the official position of Charles V, Holy Roman Emperor and King of Spain, although it was often ignored by the colonists and conquistadores themselves.
With the realization that the Americas represented regions of the Earth with which the Europeans were not aware of earlier, there arose intense speculation over the question whether the natives of these lands were true humans or not. Together with that went a debate over the (mis)treatment of these natives by the Conquistadores and colonists.
A substantial party believed that these new found peoples were not truly human. This party speculated that since Christendom was not permitted by God to become aware of their existence and thus bring the Gospel to them until so late, it was only because they were not human or possessed no souls, so they could not attain salvation. After all, the New Testament says that the gospel has been preached to all nations; since the gospel had not been preached to the Native Americans, perhaps they didn't count. In addition, Christians understood humanity to be divided into three distinct races (Europeans, Asians, and Africans), one for each of the sons of Noah. Native Americans did not fit among these divisions.
The enemy of the human race, who opposes all good deeds in order to bring men to destruction, beholding and envying this, invented a means never before heard of, by which he might hinder the preaching of God's word of Salvation to the people: he inspired his satellites who, to please him, have not hesitated to publish abroad that the Indians of the West and the South, and other people of whom We have recent knowledge should be treated as dumb brutes created for our service, pretending that they are incapable of receiving the Catholic Faith.
We, who, though unworthy, exercise on earth the power of our Lord and seek with all our might to bring those sheep of His flock who are outside into the fold committed to our charge, consider, however, that the Indians are truly men and that they are not only capable of understanding the Catholic Faith but, according to our information, they desire exceedingly to receive it. Desiring to provide ample remedy for these evils, We define and declare by these Our letters, or by any translation thereof signed by any notary public and sealed with the seal of any ecclesiastical dignitary, to which the same credit shall be given as to the originals, that, notwithstanding whatever may have been or may be said to the contrary, the said Indians and all other people who may later be discovered by Christians, are by no means to be deprived of their liberty or the possession of their property, even though they be outside the faith of Jesus Christ; and that they may and should, freely and legitimately, enjoy their liberty and the possession of their property; nor should they be in any way enslaved; should the contrary happen, it shall be null and have no effect.