This is of course, the LDS view which is not shared by other groups that originate in the Latter Day Saint movement. For examples,the Rigdonites recognize Sydney Rigdon as the legitimate successor to Smith, because he was the first counselor to Smith.
The “senior apostle” as successor is a claim that came from Young, and is not the line of succession that Smith had put into place. Smith anointed his eldest son as his successor, recorded as having done so three times. With Smith’s untimely murder, the boy was too young to lead. But here is where the RLDS claim to the correct succession lies, as the boy once grown, led that group.
Nine years before Joseph Smith’s martyrdom Jesus Christ directed Joseph Smith to establish 2 ruling bodies: The First Presidency (D&C 107:22) and the Quorum of Twelve Apostles (D&C 107:23)
D&C 107:22
Of the Melchizedek Priesthood,* three Presiding High Priests**, chosen by the body, appointed and ordained to that office, and upheld by the confidence, faith, and prayer of the church,
form a quorum of the Presidency of the Church.*
D&C 107:23
The twelve traveling councilors are called to be the Twelve Apostles, or special witnesses of the name of Christ in all the world—thus differing from other officers in the church in the duties of their calling.
Christ declared that the two bodies are equal in power and authority.
D&C 107:24
And they form a quorum, equal in authority and power to the three presidents previously mentioned.
This was reaffirmed two years later.
D&C 112:30
For unto you, the Twelve, and those, the First Presidency, who are appointed with you to be your counselors and your leaders, is the power of this priesthood given, for the last days and for the last time, in the which is the dispensation of the fulness of times,
With the martyrdom of Joseph Smith there was no First Presidency any more since its head was gone. The Twelve Apostles were the only remaining ruling body with Brigham Young its head. Brigham Young was designated the president of the Twelve Apostles in 1841.
D&C 124:127* I give unto you my servant Brigham Young to be a president over the Twelve. traveling council;*
A talk by Gordon B. Hinckley addressed these matters at a time when a transcript of a Father’s Blessing came in the possession of the LDS Church. See
lds.org/general-conference/1981/04/the-joseph-smith-iii-document-and-the-keys-of-the-kingdom?lang=eng
Note this paragraph from that talk…
First, it should be said that the document is a transcript of a blessing. It is not a record of ordination to an office. As a matter of fact, the recipient of the blessing, Joseph Smith III, himself testified in 1893, in the U.S. Circuit Court in Kansas City: “
I did not state that I was ordained by my father: I did not make that statement.
I was not ordained by my father as his successor: according to my understanding of the word ordain, I was not. I was blessed by him and designated, well in a sense chosen.
Joseph Smith III admitted in 1893 that he was never ordained to lead the LDS Church.
Regarding Priesthood Blessings, the promises made are conditional on the righteousness of the recipient.
I hope this helps…
