Article 1, Section 9, Clause 1

Document 4

Tench Coxe, An Examination of the Constitution

The importation of slaves from any foreign country is, by a clear implication, held up to the world as equally inconsistent with the dispositions and the duties of the people of America. A solid foundation is laid for exploding the principles of negro slavery, in which many good men of all parties in Pennsylvania, and throughout the union, have already concurred. The temporary reservation of any particular matter must ever be deemed an admission that it should be done away. This appears to have been well understood. In addition to the arguments drawn from liberty, justice and religion, opinions against this practice, founded in sound policy, have no doubt been urged. Regard was necessarily paid to the peculiar situation of our southern fellow-citizens; but they on the other hand, have not been insensible of the delicate situation of our national character on this subject.

The Founders' Constitution
Volume 3, Article 1, Section 9, Clause 1, Document 4
http://press-pubs.uchicago.edu/founders/documents/a1_9_1s4.html
The University of Chicago Press

Ford, Paul Leicester, ed. Pamphlets on the Constitution of the United States, Published during Its Discussion by the People, 1787--1788. Brooklyn, 1888. Reprint. New York: De Capo Press, 1968.