Shortly after D&C 1 is given, there is some question and criticism about the language in the revelations, and Joseph receives D&C 67. In it, the Lord bears witness that the revelations are from him, and challenges the wisest among the elders to write a revelation on his own to see if he can duplicate Joseph's ability. After this revelation is received, McLellin tries to write a commandment but fails. Joseph records, "It was an awful responsibility to write in the name of the Lord." After this episode, the faith of the elders is increased, and they draw up a testimony to Joseph's revelations, which can be seen in D&C, p. iv. (History of the Church of Jesus Christ of Latter-day Saints (7 volumes) 1:226.) Four elders inquire of Joseph the mind of the Lord concerning them, and he receives D&C 68.
[Conkling, Christopher J., Joseph Smith Chronology]