Bro. Joseph Smith Jun. read the 2nd Chapter of the prophecy of Joel & took the lead in prayer, after which, he commenced addressing the congregation as follows. It is very difficult for us to communicate to the churches all that God has revealed to us, in consequence of tradition; for we are differently situated from any other people that ever existed upon this Earth: Consequently those former revelations cannot be suited to our condition, because they were given to other people who were before us; but in the last days, God was to call a remnant, in which was to be deliverence, as well as in Jerusalem and Zion. Now, if God should give no more revelations, where will we find Zion and this remnant? He said that the time was near when desolation was to cover the Earth, and then God would have a place of deliverance in his remnant, and in Zion, &c. He then gave a relation of obtaining and translating the Book of Mormon, the revelation of the priesthood of Aaron, the organization of the Church in the year 1830, the revelation of the high priesthood, and the gift of the Holy Spirit poured out upon the church, &c.1
Take away the Book of Mormon, and the revelations, and where is our religion? We have none; for without a Zion and a place of deliverance, we must fall, because the time is near when the sun will be darkened, the moon turn to blood, the stars fall from heaven and the earth reel to and fro; then if this is the case, if we are not sanctified and gathered to the places where God has appointed, our former professions and our great love for the bible, we must fall, we cannot stand, we cannot be saved; for God will gather out his saints from the gentiles and then comes desolation or destruction and none can escape except the pure in heart who are gathered, &c.
[Sidney Rigdon, Oliver Cowdery and others gave short speeches]
... Bro. Joseph Smith Jun. then delivered a short prophecy, that if Zion was not delivered the time was near when all of this church, wherever they might be found, would be persecuted and destroyed in like manner.
. . . Bro. Joseph [Smith] then occupied a few minutes by way of explanation of the revelation concerning the building of the House of the Lord [D&C 95?].
1. The apparent lack of explicit mention of the visit of the ancient apostles Peter, James and John found in LDS D&C 27 before 1835 (see the note in the link) makes the incident more mysterious. The reference to "high priesthood" undoubtedly refers to the June 1831 conference. If so, the failure to mention the Peter, James and John incident suggests something like the situation with the April 3, 1836 revelation. Neither of the principals mentioned that revelation while they lived apparently, although it was recorded at the time. The date of the Peter, James and John visitation remains in question, with a wide difference of opinion. Dates range from June 1829 to 1832, perhaps the most likely date being either the summer of 1830 or June 1829. In any case, Joseph and Oliver were apparently authorized to do ordinations to the office of Elder by "the voice of God" (HC 1:62). See also this note.