Susa Young Gates quotes Joseph Smith in 1835 claiming to have authority to marry others.
"Homespun" [Susa Young Gates], Lydia Knight’s History: The First Book of the Noble Women’s Lives Series (Salt Lake City: Juvenile Instructor Office, 1883), 30-31
Thus was the first marriage ceremony ever performed by the Prophet Joseph Smith. Here was laid the foundation stone of the grand structure of our marriage ceremony. The revelation of sealing was not given, but after he had united the two he blessed them with fervor. Then turning to the company he exclaimed:
"Our Elders have been wronged and prosecuted for marrying without a license. The Lord God of Israel has given me authority to unite the people in the holy bonds of matrimony. And from this time forth I shall use that privilege and marry whomsoever I see fit. And the enemies of the Church shall never have power to use the law against me."
This was the marriage of Newell Knight and Lydia Goldthwaite Bailey in Kirtland on November 24, 1835.