And now, my son, I have somewhat to say concerning the thing which our fathers call a ball, or director—or our fathers called it Liahona, which is, being interpreted, a compass; and the Lord prepared it.
39 And behold, there cannot any man work after the manner of so curious a workmanship. And behold, it was prepared to show unto our fathers the course which they should travel in the wilderness.
40 And it did work for them according to their faith in God; therefore, if they had faith to believe that God could cause that those spindles should point the way they should go, behold, it was done; therefore they had this miracle, and also many other miracles wrought by the power of God, day by day.
41 Nevertheless, because those miracles were worked by small means it did show unto them marvelous works. They were slothful, and forgot to exercise their faith and diligence and then those marvelous works ceased, and they did not progress in their journey;
42 Therefore, they tarried in the wilderness, or did not travel a direct course, and were afflicted with hunger and thirst, because of their transgressions.
43 And now, my son, I would that ye should understand that these things are not without a shadow; for as our fathers were slothful to give heed to this compass (now these things were temporal) they did not prosper; even so it is with things which are spiritual.
44 For behold, it is as easy to give heed to the word of Christ, which will point to you a straight course to eternal bliss, as it was for our fathers to give heed to this compass, which would point unto them a straight course to the promised land.
45 And now I say, is there not a type in this thing? For just as surely as this director did bring our fathers, by following its course, to the promised land, shall the words of Christ, if we follow their course, carry us beyond this vale of sorrow into a far better land of promise.
46 O my son, do not let us be slothful because of the easiness of theway; for so was it with our fathers; for so was it prepared for them, that if they would look they might live; even so it is with us. The way is prepared, and if we will look we may live forever.
47 And now, my son, see that ye take care of these sacred things, yea, see that ye look to God and live. Go unto this people and declare the word, and be sober. My son, farewell.
Volume No. 3, Issue: 2 by 31st of July, 1994 The Design of the Liahona and the Purpose of the Second Spindle Robert L. Bunker
The Liahona was given by the Lord as a communications device for Lehi to determine the appropriate direction of travel. This device contained two pointers, only one of which was necessary to provide directional information. But the Liahona was more than just a simple compass in function, for it additionally required faith for correct operation. Since a single pointer always “points” in some direction, the additional pointer was necessary to indicate whether or not the first pointer could be relied upon. This proposed purpose for the second pointer conforms to a well-established engineering principle used in modern fault-tolerant computer systems called “voting,” in which two identical process states are compared and declared correct if they are the same, and incorrect if they are different. Hence the second pointer, when coincident with the first, would indicate proper operation, and when orthogonal, would indicate nonoperation.
Question: Was the Liahona simply a magnetic compass that was out of place in 600 B.C.?
To use the word compass as a name for a round or curved object is well attested in both the King James Version of the Bible and the Oxford English Dictionary
It is claimed that the description of the Liahona as a “compass” is anachronistic because the magnetic compass was not known in 600 B.C. One critical website notes that “the COMPASS which DIRECTED one’s course wasn’t invented yet for many centuries.” 
To use the word compass as a name for a round or curved object is well attested in both the King James Version of the Bible and the Oxford English Dictionary. The Book of Mormon refers to the Liahona as “a compass” not because it anachronistically pointed the way to travel, but because it was a perfectly round object.
1 Nephi 16:10, 30
10 And it came to pass that as my father arose in the morning, and went forth to the tent door, to his great astonishment he beheld upon the ground a round ball of curious workmanship; and it was of fine brass. And within the ball were two spindles; and the one pointed the way whither we should go into the wilderness.
30 And it came to pass that I, Nephi, did go forth up into the top of the mountain, according to the directions which were given upon the ball.
This object did give directions, however this object was referred as “a compass” because it was a perfectly round object.
The purpose of the two spindles is not explained, however, one assumes that one of them provided directional information
The fact that the Liahona is referred to as a “compass” and that it contained spindles leads one to assume that it was used like a modern compass. However, there is no indication that either of the spindles pointed to magnetic north. If one of the spindles was used to provide directional information, the inference is that it simply pointed the direction that they were to go, which would not be magnetic north.
The Book of Mormon does specifically indicate, however, that the Liahona was used to direct the travels of Lehi’s party based upon writing that appeared upon the object
As Nephi put it, the “directions which were given upon the ball”:
29 And there was also written upon them a new writing, which was plain to be read, which did give us understanding concerning the ways of the Lord; and it was written and changed from time to time, according to the faith and diligence which we gave unto it. And thus we see that by small means the Lord can bring about great things.
30 And it came to pass that I, Nephi, did go forth up into the top of the mountain, according to the directions which were given upon the ball. 1 Nephi 16:29-30 (emphasis added)
Alma 37:38–47. The Liahona
Over the years several General Authorities have described different means in which the Lord continues to guide us in our journey of life, like a Liahona.
Elder W. Rolfe Kerr of the Seventy compared the words of Christ to the Liahona: “So we see, brethren and sisters, that the words of Christ can be a personal Liahona for each of us, showing us the way. Let us not be slothful because of the easiness of the way. Let us in faith take the words of Christ into our minds and into our hearts as they are recorded in sacred scripture and as they are uttered by living prophets, seers, and revelators. Let us with faith and diligence feast upon the words of Christ, for the words of Christ will be our spiritual Liahona telling us all things what we should do” (in Conference Report, Apr. 2004, 38; or Ensign, May 2004, 37).
President Thomas S. Monson compared the Liahona to an individual’s patriarchal blessing: “The same Lord who provided a Liahona for Lehi provides for you and for me today a rare and valuable gift to give direction to our lives. … The gift to which I refer is known as a patriarchal blessing” (Live the Good Life , 36).
President Spencer W. Kimball compared the Liahona to the light of Christ, or our conscience:
“Wouldn’t you like to have that kind of a ball … ?
“… The Lord gave to … every person, a conscience which tells him everytime he starts to go on the wrong path. …
“… Every child is given it” (in Conference Report, Oct. 1976, 117; or Ensign, Nov. 1976, 79).
Elder David A. Bednar compared the Liahona to the gift of the Holy Ghost:
“As we each press forward along the pathway of life, we receive direction from the Holy Ghost just as Lehi was directed through the Liahona. …
“The Holy Ghost operates in our lives precisely as the Liahona did for Lehi and his family, according to our faith and diligence and heed. …
“And the Holy Ghost provides for us today the means whereby we can receive, ‘by small and simple things’ (Alma 37:6), increased understanding about the ways of the Lord. …
“The Spirit of the Lord can be our guide and will bless us with direction, instruction, and spiritual protection during our mortal journey” (in Conference Report, Apr. 2006, 31; or Ensign, May 2006, 30–31).
This 13th century frontispiece from the Codex Vindobonensis 2554 shows God as creator using a compass—so named not because it is used for navigation, but because it is used to draw arcs and circles.
Alma2 explained why the director the Lord gave to Lehi was called the Liahona
…I have somewhat to say concerning the thing which our fathers call a ball, or director — or our fathers called it Liahona, which is, being interpreted, a compass; and the Lord prepared it (Alma 37:38).
Believing it was called a compass because it pointed the direction for Lehi to travel is a natural interpretation by the modern reader
As a verb, the word “compass” occurs frequently in the King James Version of the Bible; and it generally suggests the idea of surrounding or encircling something. Note the following usages:
Also he made a molten sea of ten cubits from brim to brim, round in compass, and five cubits the height thereof; and a line of thirty cubits did compass it round about. 2 Chronicles 4:2
They compassed me about; yea, they compassed me about: but in the name of the Lord I will destroy them. Psalms 118:11
And ye shall compass the city, all ye men of war, and go round about the city once. Thus shalt thou do six days. Joshua 6:3
From the wicked that oppress me, from my deadly enemies, who compass me about. Psalms 17:9
A third common situation in the KJV is the use of the phrase “to fetch a compass” (e.g., Numbers 34:5; Joshua 15:3; Acts 28:13), which if not recognized as a verbal phrase could be wrongly seen as presenting “compass” as a noun.
In every case, it is clear that, at least in Jacobean England, the word was regularly treated as meaning either a round object, or something which moved in a curved fashion. The Book of Mormon text uses a form of Jacobean English–and does not contain expressions that were introduced after 1700. This has implications for how we read the text. The critic treats something important as insignificant.
Further evidence of the archaic meaning of the word comes from a study of the rather lengthy listing for the word in the Oxford English Dictionary. It includes definition 5.b.:
“Anything circular in shape, e.g. the globe, the horizon; also, a circlet or ring.”
the clock can also be referred to as a compass, yet it points at the time.
If critics insist on reading this as a “mariner’s compass,” even this may not be as anachronistic as they have assumed
Non-LDS astronomer John Carlson reported finding a Olmec hematite artifact in Mesoamerica, which was radio-dated to 1600 to 1000 B.C. If Carlson is right, this usage “predates the Chinese discovery of the geomagnetic lodestone compass by more than a millennium.” Other researchers have suggested the metal is simply part of an ornament, though Mesoamericanist Michael Coe has suggested the use of such ores as floating compasses. Such examples demonstrate how a single find can radically alter what archaeology tells us is “impossible” with regard to the Book of Mormon text.
As Robert F. Smith observed:
it is worth noting that the function of magnetic hematite was well understood in both the Old and New Worlds before Lehi left Jerusalem. Magnetite, or lodestone, is, of course, naturally magnetic iron (Fe3O4), and the word magnetite comes from the name of a place in which it was mined in Asia Minor by at least the seventh century B.C., namely Magnesia.[a] Parenthetically, Professor Michael Coe of Yale University, a top authority on ancient Mesoamerica, has suggested that the Olmecs of Veracruz, Mexico, were using magnetite compasses already in the second millennium B.C. This is based on Coe’s discovery during excavations at San Lorenzo-Tenochtitlán of a magnetite “pointer” which appeared to have been “machined,” and which Coe placed on a cork mat in a bowl of water in a successful test of its function as a true floater-compass.[b] The Olmecs (Jaredites?) of San Lorenzo and their relatives in the Oaxaca Valley were utilizing natural iron ore outcroppings by the Early Formative period (c. 1475-1125 B.C.), and at the end of the San Lorenzo phase and in the Nacaste phase (c. 1200-840 B.C.). Mirrors and other items were also fashioned from this native magnetite (and ilmenite).