Washings and anointings are associated.
Defines what an endowment is.
Required for full exaltation.
- Discourses of Brigham Young, sel. John A. Widtsoe (1941), 416
Cited in Boyd K. Packer, “Come to the Temple,” Ensign, Oct 2007, 18–22
"Let me give you a definition in brief. Your endowment is, to receive all those ordinances in the house of the Lord, which are necessary for you, after you have departed this life, to enable you to walk back to the presence of the Father, passing the angels who stand as sentinels, being enabled to give them the key words, the signs and tokens, pertaining to the holy Priesthood, and gain your eternal exaltation in spite of earth and hell."
- Joseph Smith, compiled by Joseph Fielding Smith, "Teachings of the Prophet Joseph Smith", p. 90-91
(To the 12 Apostles and his counselors.)
The Apostles were not yet able to comprehend the endowment.
Fault-finding precludes their obtaining the endowment.
Endowment necessary to enable them to overcome all things and will facilitate healings and the damnation of those that reject their testimonies.
The endowment adds responsibility to warn all and bear testimony.
(I expect the added responsibility has something to do with the greater ability and preparation they would have.)