I thought perhaps I should add a bit more with scriptural support since the copy-and-paste provides some ease.
Moses 5: 4-7. 16-25
4 And Adam and Eve, his wife, called upon the name of the Lord, and they heard the voice of the Lord from the way toward the Garden of Eden, speaking unto them, and they saw him not; for they were shut out from his presence.
5 And he gave unto them commandments, that they should worship the Lord their God, and should offer the firstlings of their flocks, for an offering unto the Lord. And Adam was obedient unto the commandments of the Lord.
6 And after many days an angel of the Lord appeared unto Adam, saying: Why dost thou offer sacrifices unto the Lord? And Adam said unto him: I know not, save the Lord commanded me.
7 And then the angel spake, saying: This thing is a similitude of the sacrifice of the Only Begotten of the Father, which is full of grace and truth.
. . .
16 And Adam and Eve, his wife, ceased not to call upon God. And Adam knew Eve his wife, and she conceived and bare Cain, and said: I have gotten a man from the Lord; wherefore he may not reject his words. But behold, Cain hearkened not, saying: Who is the Lord that I should know him?
17 And she again conceived and bare his brother Abel. And Abel hearkened unto the voice of the Lord. And Abel was a keeper of sheep, but Cain was a tiller of the ground.
18 And Cain loved Satan more than God. And Satan commanded him, saying: Make an offering unto the Lord.
19 And in process of time it came to pass that Cain brought of the fruit of the ground an offering unto the Lord.
20 And Abel, he also brought of the firstlings of his flock, and of the fat thereof. And the Lord had respect unto Abel, and to his offering;
21 But unto Cain, and to his offering, he had not respect. Now Satan knew this, and it pleased him. And Cain was very wroth, and his countenance fell.
22 And the Lord said unto Cain: Why art thou wroth? Why is thy countenance fallen?
23 If thou doest well, thou shalt be accepted. And if thou doest not well, sin lieth at the door, and Satan desireth to have thee; and except thou shalt hearken unto my commandments, I will deliver thee up, and it shall be unto thee according to his desire. And thou shalt rule over him;
24 For from this time forth thou shalt be the father of his lies; thou shalt be called Perdition; for thou wast also before the world.
25 And it shall be said in time to come — That these abominations were had from Cain; for he rejected the greater counsel which was had from God; and this is a cursing which I will put upon thee, except thou repent.
Gen. 4: 13-15
13 And Cain said unto the Lord, My punishment is greater than I can bear.
14 Behold, thou hast driven me out this day from the face of the earth; and from thy face shall I be hid; and I shall be a fugitive and a vagabond in the earth; and it shall come to pass, that every one that findeth me shall slay me.
15 And the Lord said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the Lord set a mark upon Cain, lest any finding him should kill him.
We read from above about Cain's corruption of the priesthood ordinance symbolizing the Great Sacrifice. They were commanded to offer the firstlings of their flocks, which offering was a similitude of the sacrifice of the Only Begotten of the Father. But Cain made his own variation of the ordinance - "Cain brought of the fruit of the ground an offering unto the Lord."
Cain could not be trusted regarding priesthood matters. "The Lord had respect unto Abel, and to his offering; But unto Cain, and to his offering, he had not respect."
Cain disregarded the sacrifice of the Only Begotten of the Father. As a priest, who was called to perform the ordinance in which a similitude of the sacrifice of the Only Begotten of the Father was offered, Cain failed miserably. Cain disregarded the sacred things of the priesthood; and therefore the priesthood authority was withdrawn from Cain.
Cain was called Perdition. This was apparently the kind of spirit that he was before he was born. The scripture says "for thou wast also before the world."
Cain became the father of people who perpetuated the "abominations' that "were had from Cain". The people who were born in the lineage of Cain were born in the lineage of Cain because they were very much of the same spirit as Cain's before they were born into the world. Cain's lineage perpetuated the abominations and the curse was continued; they bore the mark of the curse and they were denied the priesthood authority because they cannot be trusted.
A similar disregard of the sacred things of the priesthood was perpetuated by Ham after the flood; and the mark of the curse which is the "blackness" was brought on Canaan, which again ordained a lineage into which rebellious spirits were born - because these spirits must have been rebellious like Cain before they came into the world.
Gen. 9: 18-27
18 And the sons of Noah, that went forth of the ark, were Shem, and Ham, and Japheth: and Ham is the father of Canaan.
19 These are the three sons of Noah: and of them was the whole earth overspread.
20 And Noah began to be an husbandman, and he planted a vineyard:
21 And he drank of the wine, and was drunken; and he was uncovered within his tent.
22 And Ham, the father of Canaan, saw the nakedness of his father, and told his two brethren without.
23 And Shem and Japheth took a garment, and laid it upon both their shoulders, and went backward, and covered the nakedness of their father; and their faces were backward, and they saw not their fatherÂ’s nakedness.
24 And Noah awoke from his wine, and knew what his younger son had done unto him.
25 And he said, Cursed be Canaan; a servant of servants shall he be unto his brethren.
26 And he said, Blessed be the Lord God of Shem; and Canaan shall be his servant.
27 God shall enlarge Japheth, and he shall dwell in the tents of Shem; and Canaan shall be his servant.
Moses 7: 8
8 For behold, the Lord shall curse the land with much heat, and the barrenness thereof shall go forth forever; and there was a blackness came upon all the children of Canaan, that they were despised among all people.
The land was actually cursed with so much melanin-producing heat and a blackness came upon the children of Canaan that they were particularly despised among all people.
As far as I know the mark of the curse and its meaning as pertains the descendants of Canaan was never lifted by any sacred pronouncement until the 1978 declaration of a revelation to Pres. Spencer W. Kimball of the Mormon Church.
The mark of the curse was also placed on the Lamanites who disregarded the sacred things of the priesthood. The Lamanites sought to destroy those who honored the priesthood.
Alma 3: 7 (7-16)
7 And their brethren sought to destroy them, therefore they were cursed; and the Lord God set a mark upon them, yea, upon Laman and Lemuel, and also the sons of Ishmael, and Ishmaelitish women.
And then the mark of the curse was erased when everyone became very righteous after the visit of the resurrected Christ.
4 Nephi 1: 17, 20
17 There were no robbers, nor murderers, neither were there Lamanites, nor any manner of -ites; but they were in one, the children of Christ, and heirs to the kingdom of God.
However, after a while, again there came a great divide among the people; the people grouped themselves into Nephites and Lamanites and they had terrible wars that practically annihilated the Nephites and only "Lamanites" were left alive. These again became a dark, filthy and loathsome people.
Mormon 5: 15
15 And also that the seed of this people may more fully believe his gospel, which shall go forth unto them from the Gentiles; for this people shall be scattered, and shall become a dark, a filthy, and a loathsome people, beyond the description of that which ever hath been amongst us, yea, even that which hath been among the Lamanites, and this because of their unbelief and idolatry.
But there was no more mention of any curse put upon them as pertaining to the priesthood restrictions - except that there is mention that they became idolatrous unbelievers, which means they had no worthy priesthood holders.
The latter-day leaders actually acknowledged the scriptural stipulations regarding the curse associated with the skin of blackness, especially as eprtains the descendants of Canaan (which I think was understood to be the African people). The blacks were 'generally' not ordained the priesthood authority and could not therefore administer the priesthood ordinances.
Like the Canaanite woman who implored the Lord, they were allowed certain blessings - like that in the ordinances for the forgiveness of sins. But they were not allowed the ordinances for exaltation since these entailed that they be entrusted the priesthood authority to administer the priesthood ordinances. This is of course until the 1978 declaration.
I was already a convert to the Mormon Church many years before the 1978 declaration regarding the priesthood for the black people. It was not a surprise or an extraordinarily difficult issue for us. We were satisfied by the scriptural explanations and personal spiritual confirmations regarding the 1978 declaration.
The Lord must have deemed it prudent for the Church to not have black priesthood holders during the time when blacks were generally slaves and when the black culture was pretty much un-enticing. This ended of course when the black people gained enough social respectability and also the honor before the Lord (circa 1978).
In sum, I think the terms "racist/racism", "racial discrimination" and "racial prejudice" should be understood and used correctly.
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As for the science thing, I actually like the science ideas mixed with the religion (e.g., among my faves is "kinematic relativity" as reconciled with LDS ideas ) -
The religion of the Latter-day Saints is not hostile to any truth, nor to scientific search for truth. "That which is demonstrated, we accept with joy," said the First Presidency in their Christmas greeting to the Saints, "but vain philosophy, human theory and mere speculations of men we do not accept, nor do we adopt anything contrary to divine revelation or to good common sense, but everything that tends to right conduct, that harmonizes with sound morality and increases faith in Deity, finds favor with us, no matter where it may be found." ["Words in Season from the First Presidency," Deseret Evening News, 17 Dec. 1910, 3.]
I do not see how the idea of the evolution of man from the apes "tends to right conduct,.. harmonizes with sound morality and increases faith in Deity."
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