This revelation was given to Prophet Joseph Smith in 1831 and can be found here in Doctrine and Covenants 1:30.
I ask this question because the entire body of Mormonism, 100% of its "scriptural" content (apart from its borrowings from the Bible) is fully and exclusively traceable to and or dependent upon exactly and only one source: the claims of one man - Joseph Smith. He is the single, sole source of the Mormon "revelation," why should we believe him? Why do Mormons believe him?
Here is a brief quote from an official LDS source on the priesthood that mentions two Bible passages to support their belief that theirs is the only true church:
“When Jesus Christ was on the earth, He established His Church and gave His Apostles the priesthood, which is the power to act in His name (see Luke 9:1–2). After His Crucifixion and the death of His Apostles, priesthood authority and the fulness of the gospel were taken from the earth because of wickedness and a rejection of the truth (see 2 Thessalonians 2:1–3).”
This is what Luke 9:1-2 (NIV) says:
When Jesus had called the Twelve together, he gave them power and authority to drive out all demons and to cure diseases, and he sent them out to preach the kingdom of God and to heal the sick.
This is what 2 Thessalonians 2:1-3 (NIV) says:
Concerning the coming of our Lord Jesus Christ and our being gathered to him, we ask you, brothers, not to become easily unsettled or alarmed by some prophecy, report or letter supposed to have come from us, saying that the day of the Lord has already come. Don’t let anyone deceive you in any way, for that day will not come, until the rebellion occurs and the man of lawlessness is revealed, the man doomed to destruction.
Although the quote below is not taken from the Bible, it goes some way to explaining the LDS view:
During the time of the Apostasy, precious doctrines were lost from the Bible through carelessness, uninspired translation, or deliberate efforts to erase the truth. A restoration of that lost doctrine and truth was necessary. The Book of Mormon and other scripture revealed to the Prophet Joseph Smith brought back many of those plain and precious parts of the gospel....
Today we can be members of “the only true and living church upon the face of the whole earth” (D&C 1:30) because the Lord restored His gospel and conferred priesthood authority to the Prophet Joseph Smith to organize His Church (see D&C 27; D&C 65; D&C 128:18–21). We are blessed to live in this time, when the gospel in its fulness has been restored—a time when you can go to church, bear your testimony, and read the scriptures."
Because the LDS eighth article of faith says, “We believe the Bible to be the word of God as far as it is translated correctly” perhaps that is why they rely on the Book of Mormon?
Another LDS article about the restoration of the gospel through Joseph Smith has this to say:
“In the early 1800s, Heavenly Father and Jesus Christ restored the gospel to the earth through the Prophet Joseph Smith. This Restoration included the restoration of priesthood power and authority.
While Joseph Smith and Oliver Cowdery were working on the translation of the Book of Mormon, they read about baptism for the remission of sins. On May 15, 1829, they went to a wooded area near Joseph’s home in Harmony, Pennsylvania, and prayed about what they had learned.
In answer to their prayer, John the Baptist, under the direction of the Lord Jesus Christ, appeared and conferred upon them the Aaronic Priesthood, saying, “Upon you my fellow servants, in the name of Messiah I confer the Priesthood of Aaron, which holds the keys of the ministering of angels, and of the gospel of repentance, and of baptism by immersion for the remission of sins” (Doctrine and Covenants 13:1) ...
Sometime after John the Baptist’s appearance, the ancient Apostles Peter, James, and John also appeared to Joseph and Oliver, again under the direction of Jesus Christ, and conferred upon them the Melchizedek Priesthood (see Doctrine and Covenants 128:20). “The Melchizedek Priesthood holds the right of presidency, and has power and authority over all the offices in the church in all ages of the world, to administer in spiritual things” (Doctrine and Covenants 107:8). With this authority again on the earth, the Church of Jesus Christ could be restored in its fulness.”
Unfortunately, I have been unable to find any reference from the Holy Bible but I continue to look.
There is no pure 100% biblical basis for any denomination, can't prove a church is true based on the bible (see that there are more than 2 Christian denominations). Many of the Church of Jesus Christ of Latter-day Saints doctrine can be found in the bible (listing them all would be very lengthy). Many others are not and can be found in other scripture, such as the Book of Mormon, Doctrine and Covenants, or Pearl of Great Price.
The Church of Jesus Christ of Latter-day Saints believe the bible foretells of an apostasy (see answer on the significance)
Behold, the days come, saith the Lord God, that I will send a famine in the land, not a afamine of bread, nor a bthirst for water, but of hearing the cwords of the Lord:...
And ye shall hear of wars and rumours of wars: see that ye be not troubled: for all these things must come to pass, but the end is not yet. ... And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come.
that after my departing shall grievous wolves enter in among you, not sparing the flock. 30 Also of your own selves shall men arise, speaking perverse things, to draw away disciples after them.
For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears; 4 And they shall turn away their ears from the truth, and shall be turned unto fables.
If you accept that there was a falling away or an apostasy, then those churches that persisted through that time after Jesus, have strayed from the truth to some degree or another (otherwise its not a falling away) (see related Answer to Do LDS believe other churches to be the church of Satan?) If there was a falling away a restoration was needed. (see also Why was a Restoration necessary?, What does Mormonism have to offer in regards to salvation...)
From 2020 Proclamation: The Restoration of the Fulness of the Gospel of Jesus Christ
We affirm that under the direction of the Father and the Son, heavenly messengers came to instruct Joseph and re-establish the Church of Jesus Christ. The resurrected John the Baptist restored the authority to baptize by immersion for the remission of sins. Three of the original twelve Apostles—Peter, James, and John—restored the apostleship and keys of priesthood authority. Others came as well, including Elijah, who restored the authority to join families together forever in eternal relationships that transcend death.
...
We testify that those who prayerfully study the message of the Restoration and act in faith will be blessed to gain their own witness of its divinity and of its purpose to prepare the world for the promised Second Coming of our Lord and Savior, Jesus Christ.
There are other scriptures that LDS believe prophesy of Joseph Smith:
foolish things of the world could easily be a 14 year old boy to confound the wise or established churches, and God hath chosen the weak things of the world to confound the things which are mighty;)Joseph Smith's story/experience are very profound. Either they happened and are true, or they didn't and it's all false. The Book of Mormon can stand as a witness for itself of its truthfulness (and has additional witnesses to its existence), which leaves the primary translator to be questioned. Many non believers are under the impression if they can tear down Joseph Smith's character it'll lead to the collapse of the Church of Jesus Christ.
From Truman G Madsen Joseph Smith and Trials
Persecutors did do unto him and his brothers as they had done unto the Lord. They fought, they vilified, they attacked. They perceived him as a threat to them, and they did all within their power to stop him.
On the claims that 100% of scriptural content came from Joseph Smith and that he is the single, sole source of the Mormon "revelation, this isn't true. The Doctrine and Covenants contains writings of Oliver Cowdery (D&C 6, D&C 9, D&C 18, D&C 110), David Whitmer (D&C 18), Brigham Young (D&C 136), John Taylor (D&C 135), Wilford Woodruff (Official Declaration 1), Lorenzo Snow(Official Declaration 1), Joseph F Smith (D&C 138), Spencer W Kimball (Official Declaration 2) (names quickly ref from @HoldToTheRod)
Including the 6 official proclamations, the list expands.
If you expand further to include general revelation the number of people in the list becomes very long (Bi-annual General Conference).
