God has commanded us not to contend with each other:
For verily, verily I say unto you, he that hath the spirit of contention is not of me, but is of the devil, who is the father of contention, and he stirreth up the hearts of men to contend with anger, one with another. (3 Nephi 11:29)
Yet, not all argument is contention. The word “argue” sometimes connotes anger and disrespect, and not just in modern context. Lehi explained to Laman and Lemuel that they were incorrect in assuming that Nephi's arguments towards them were motivated by anger:
25 And I exceedingly fear and tremble because of you, lest he shall suffer again; for behold, ye have accused him that he sought power and authority over you; but I know that he hath not sought for power nor authority over you, but he hath sought the glory of God, and your own eternal welfare.
26 And ye have murmured because he hath been plain unto you. Ye say that he hath used sharpness; ye say that he hath been angry with you; but behold, his sharpness was the sharpness of the power of the word of God, which was in him; and that which ye call anger was the truth, according to that which is in God, which he could not restrain, manifesting boldly concerning your iniquities.
27 And it must needs be that the power of God must be with him, even unto his commanding you that ye must obey. But behold, it was not he, but it was the Spirit of the Lord which was in him, which opened his mouth to utterance that he could not shut it. (2 Nephi 1)
Arguments, then, are not contentious by definition, but only when they are motivated by anger. Even here, we have to separate the subtle difference between anger and “sharpness.” Arguing truth for the purpose of persuasion can include sharpness (see D&C 121:43). In fact, Jesus frequently employed sharpness. In one typical example, he said:
39 And the Lord said unto him, Now do ye Pharisees make clean the outside of the cup and the platter; but your inward part is full of ravening and wickedness.
40 Ye fools, did not he that made that which is without make that which is within also?
41 But rather give alms of such things as ye have; and, behold, all things are clean unto you.
42 But woe unto you, Pharisees! for ye tithe mint and rue and all manner of herbs, and pass over judgment and the love of God: these ought ye to have done, and not to leave the other undone.
43 Woe unto you, Pharisees! for ye love the uppermost seats in the synagogues, and greetings in the markets.
44 Woe unto you, scribes and Pharisees, hypocrites! for ye are as graves which appear not, and the men that walk over them are not aware of them.
45 Then answered one of the lawyers, and said unto him, Master, thus saying thou reproachest us also.
46 And he said, Woe unto you also, ye lawyers! for ye lade men with burdens grievous to be borne, and ye yourselves touch not the burdens with one of your fingers.
47 Woe unto you! for ye build the sepulchres of the prophets, and your fathers killed them.
48 Truly ye bear witness that ye allow the deeds of your fathers: for they indeed killed them, and ye build their sepulchres. (Luke 11)
How would you react if someone called you a fool, full of wickedness, a hypocrite, and a murderer? Would you consider that contention? Yet, Jesus’ example shows it is not. While it is true that Jesus was gentle with the meek, he was also very sharp with the prideful. Joseph Smith said:
I have not the least idea, if Christ should come to the earth and preach such rough things as He preached to the Jews, but that this generation would reject Him for being so rough. (History of the Church, 5:423)
Jesus is the perfect example to follow. You can't emulate Jesus without arguing and, at times, with sharpness. Sharpness is often the only way to crack through false tradition, an ideological film that is almost always based on an inherited position (by definition, one not based on reasoning or evidences, but an emotive connection). It is very difficult to reason with someone who is arguing from an emotive position.
The definition of “argue” is “to give reasons or cite evidence in support of an idea, action, or theory, typically with the aim of persuading others to share one's view.” When argument is used in the literal sense of the word, the intrinsic motivation will always be persuasion. Argue is the best word to describe how one persuades: producing evidence; reasoning. In contrast, to contend means to strive in order to prove one's position is correct; to defend one's position in order to preserve it, or to oppose. All of these senses have at their heart the intent to remain in one's former position— not, as in the case of argument or debate, to seek out truth, even if it means letting go of one's former position. Contention, then, is not the presence of argument, but the lack thereof, where an individual refuses to give or receive reasons supporting a position.
Contention is about who is right, whereas debate is about what is right. Two persons who are unwilling to change their current position are unable to argue—unable to present evidence to determine what is right. They must take turns asserting who is right. They can only contend with one another. Contention is enmity: the state or feeling of being actively opposed or hostile to someone or something. It is a feeling, not a position informed by reasoning or evidences. It is a non-neutral, non-objective, emotional, irrational practice. It is a reaction against a position rather than a defense against the evidences or reasons behind that position.
If you want to teach truth, you cannot have a contentious attitude.