Devery Anderson transcribes account of the First Presidency and Quorum of the Twelve Apostles report containing symbolism and significance of the marks on temple garments.
George F. Richards, Joseph Fielding Smith, Stephen L Richards, and Melvin J. Ballard, Committee Report to the First Presidency and Council of the Twelve Apostles, April 22, 1936 in Devery S. Anderson, ed. The Development of LDS Temple Worship, 1846–2000: A Documentary History (Salt Lake City, UT: Signature Books, 2011), pp. 242–243
We recommend that a definition be given in the temple of the symbolism and significance of the various marks in the garment. We believe that an understanding on the part of those entitled to wear the garment of these sacred markings will tend greatly to bring about more reference for the garment itself. The best interpretation which has come to us up to this time has been supplied by President [David O.] McKay. It is as follows:
A. The square: Honor, integrity, loyalty, trustworthiness.
B. The compass: An undeviating course in relation to truth. Desires should be kept within proper bounds.
C. The navel: That the spiritual life needs constant sustenance.
D. The knee: Rever[e]nce for God, the source of divine guidance and inspiration.
To this last one might be added that which is now in use: That every knee shall bow and every tongue confess that Jesus is the Christ.
All concur in this recommendation. . . .
—George F. Richards, Joseph Fielding Smith, Stephen L Richards, and Melvin J. Ballard, Committee Report to the First Presidency and Council of the Twelve Apostles, April 22, 1936