What is The Latter Rain? It is the “extra oil” “that other angel” “the additional Light”, brought forth in power, at the commencement of the time of trouble, when you cannot buy your “daily bread”. What is this Light, that lightens the whole earth with It’s Glory? It is The Name of The Most High, that inhabiteth eternity, and Whose Name is Qodesh. And the “sabbath more fully” with His Name stamped upon His True Sabbaths as a “Seal” of His Truth.
Malachi 3:16  Then they that feared Yehovah spake often one to another: and Yehovah hearkened, and heard it, and a book of remembrance was written before Him for them that feared Yehovah, and that thought upon His Name.
Malachi 3:17  And they shall be Mine, saith Yehovah of hosts, in that day when I make up my jewels;(The Sealing) and I will spare them, as a man spareth his own son that serveth him(Philadelphia is spared from the 7 last plagues).
Mal 3:18  Then shall ye return, and discern between the righteous and the wicked, between him that serveth Elohim and him that serveth Him not.(after the 144,000 are sealed and perfectly united)
These last verses in the old Testament, show us that the Sealing Truth in the Latter Rain is about worship and worshipping at the correct Address, that is “Yehovah”.
It is the Light also of His “Modeim” upon which His Name is stamped as a seal. It is the Light of His True Health Reform message, which also has the seal of His Name in Psalms 68:4, at which the saints shout “HalleluYah”. It is not the SDA hospital worldly system. And as Ellen White tells us “Each Sabbath Institution, both True and false, bears The Name of It’s Author, an Ineffaceable Mark, showing the Authority of Each”
It is “The Sabbath more fully”, The Divinely ordained Sabbath, or the True 4th Command, still unchanged on the tablets of stone, of which one of the four angels still guarding the ark, told Ron Wyatt, will be brought forth when the Sunday law, is enforced. (or Solar only calendar,) refusing us liberty to keep the lunar calendar moeds,
  It contains, the 4th Original Commandment, “Mark even Day, The New Moon, to Consecrate It”, as the first line of the 4th Commandment.
It is “at the time appointed, the end shall be” at the fulfillment of the 2300 day prophecy, when the sanctuary, mistranslated, there, which is the Hebrew word “qodesh”, or “most holy day”, shall be repaired, which we are called, “the repairers of the breach, the restorer of paths to dwell in”.
Yes the breach of all translations, including the masoretic text, from “New Moon” to “Sabbath”. Restoring the “True Sabbath Institution” Ellen White speaks of, from the false institution of the planetary week, to the Divinely instituted “Lunar Week”.
This is as Ellen White tells us, “The breach made in The Law, at the time the Sabbath was changed by man, is to be repaired” by the “other angel” which will lighten the earth with His Glory, the Glory of His Name.
  The Divinely ordained, lunar-based weekly cycle, 4 continuous weekly cycles per lunar month. “Mark even Day, The New Moon, to consecrate It.” “Six days shalt thou labor and do all thy work.” “And day, the 7th is Shabat unto Yehovah thy Elohim.” “In it thou shalt not do any work. Thou nor thy son nor thy daughter, thy manservant nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates. For in six days, Yehovah made heaven and earth, the sea, and all that in them, and rested the 7th Day, wherefore Yehovah blessed the Shabat Day and sanctified It.
  This is the “Sabbath Institution”, a calendar displayed in the heavens, of which Ellen White speaks of.
“the principles that rule in the heavens”

The picture at the top of this page, is the Hebrew Name that bears His Sabbaths as in Ellen White’s edited Holy Name quote below.
S.D.A. Bible Commentary
Vol. 7-CN- REV14-CT- Revelation-PR- 07-PG- 977

(Ch. 7:2, 3). The Question Before Us Now. –The Sabbath question is to be the issue in the great final conflict, in which all the world will act a part. Men have honored Satan’s principles above the principles that rule in the heavens.(see Gen. 1:14) They have accepted the spurious sabbath, which Satan has exalted as the sign of his authority. But YHVH Elohim has set His Seal upon His Royal Requirement. Each Sabbath institution, both true and false, bears the name of its author, an ineffaceable mark that shows the authority of each.

 see http://sda-online.com/images/leviticus-1_1.jpg

From “A Word to the Little Flock”
And at the commencement of the time of trouble, we were filled with the Holy Ghost as we went forth[L HO. 6: 2,3.] and proclaimed the Sabbath more fully. This enraged the church, and nominal Adventists, as they could not refute the Sabbath truth. And at this time, Elohim’s chosen, all saw clearly that we had the truth, and they came out and endured the persecution with us.