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Pergunta: O que o artigo número 5 das Palestras Sobre a Fé diz sobre a natureza de Deus?
Question: What does Lecture 5 of the Lectures on Faith say about the nature of God?
the Lectures did not have a trinitarian view of God—the Father and the Son were clearly distinct personages, united in mind by the Holy Spirit
Lecture 5 deals with the nature of God the Father, His Son Jesus Christ, and the Holy Ghost. Lecture 5.2 teaches:
There are two personages who constitute the great, matchless, governing, and supreme power over all things—by whom all things were created and made that are created and made, whether visible or invisible; whether in heaven, on earth, or in the earth, under the earth, or throughout the immensity of space. They are the Father and the Son: The Father being a personage of spirit, glory, and power, possessing all perfection and fullness. The Son, who was in the bosom of the Father, a personage of tabernacle, made or fashioned like unto man, or being in the form and likeness of man—or rather, man was formed after his likeness and in his image. He is also the express image and likeness of the personage of the Father, possessing all the fullness of the Father, or the same fullness with the Father, being begotten of him;(emphasis added.) 
Efforts to see this as evidence for an essentially 'trinitarian' view, are flawed
Efforts to see this as evidence for an essentially 'trinitarian' view, are flawed,  though at least one LDS missionary used this lecture to argue against the idea that God the Father and Christ "were two distinct personages, with similar bodies and minds."  Despite this claim, however, the question-and-answer section of the 5th Lecture on Faith include the following:
How many personages are there in the Godhead[?]
Two: the Father and Son.
Clearly then, as we will see below, this missionary's statement does not reflect the entirety of LDS thought on the Godhead up to that point. Ironically, his interlocutor's response harmonizes better with the Lecture's catechism and present-day LDS thought.  It is perhaps not surprising that the missionary let his critic have the last word, despite promising to address further issues! (This exchange provides an excellent lesson for apologists—when one makes a mistake or misstatement, one should admit it, and not try to salvage a bad argument.)
The role of the Holy Ghost was less clear at this point in time
The Lecture describes the "Only Begotten of the Father possessing the same mind with the Father, which mind is the Holy Spirit" (emphasis added).
The exact nature of the relationship between the Spirit and the Father and the Son was not explicitly stated until 1843:
The Father has a body of flesh and bones as tangible as man's; the Son also; but the Holy Ghost has not a body of flesh and bones, but is a personage of Spirit. Were it not so, the Holy Ghost could not dwell in us.D&C 130:22
Thus, the Lectures did not have a trinitarian view of God—the Father and the Son were clearly distinct personages, united in mind by the Holy Spirit.
The Lectures on Faith clearly taught that the Father and Son were "embodied," with visible forms having precise dimensions and position in space
After exploring the early evidence for Joseph's belief in an embodied Father, Son, and Holy Ghost (whether in flesh or spirit bodies), one author concluded:
What, then, shall be made of the lecture’s referring contrastingly to the Father as "a personage of spirit" and to the Son as "a personage of tabernacle"? Again, Webster’s 1828 dictionary is helpful. It lists "our natural body" as one use of the term tabernacle. Our natural body, I take it, is a body of flesh and bones. If so, the lectures affirm that God the Son has a flesh-and-bones body, humanlike in form, while God the Father has a spirit body, also humanlike in form. As mentioned, Joseph later knew that the Father, as well as the Son, has a glorious, incorruptible body of flesh and bone. No doubt, his understanding of the mode of the Father’s embodiment was enlarged and refined as he continued to receive and reflect on revelation. 
The Lectures on Faith clearly taught a separation of the Father and Son. They also clearly taught that the Father and Son were "embodied," with visible forms having precise dimensions and position in space. Evidence from the Book of Mormon, Doctrine and Covenants, Church members, and the Church's antagonists all demonstrate that these doctrines go back to the earliest days of the Restoration. (This is not surprising, given that Joseph's First Vision would have made the separate nature of the Godhead crystal clear.)
Whether Joseph Smith understood at this point that the Father had a physical body (as distinct from a spirit body upon which man's body was patterned) is not entirely clear, although some, such as Bruce R. McConkie, believe there is a basis for such in the Lectures on Faith. One thing is for certain, Joseph clearly did not believe in the non-embodied God of classical trinitarianism. Nor did Joseph teach of a Father and Son "of one substance" as the trinitarian creeds of his day defined them.
- Lectures on Faith Num 5, 5:2a-5:2e
- See David L. Paulsen, "The Doctrine of Divine Embodiment: Restoration, Judeo-Christian, and Philosophical Perspectives," Brigham Young University Studies 35 no. 4 (1995–96), 6–94. PDF link (Key source)
- Stephen Post, “Mormon Defence.--No. II,” Christian Palladium (Union Mills, New York) 6, no. 15 (1 December 1837): 230–31. off-site
- Oliver Barr, “Mormonism--No. V,” The Christian Palladium (Union Mills, New York) 6, no. 18 (15 January 1838): 275. off-site
- See David L. Paulsen, "The Doctrine of Divine Embodiment: Restoration, Judeo-Christian, and PhilosophicalPerspectives," Brigham Young University Studies 35 no. 4 (1995–96), 6–94. PDF link