Mixco Viejo, a ruined city in what is now Guatemala, had its beginnings as early as A.D. 900. Once home to some 1,500 people, the impressive city was fortified by surrounding hills and steep approaches on all sides.

According to legend, Spanish conquistador Pero Alvarado laid siege to the protected city in 1525. The Spanish suffered great losses as they tried for more than a month to take Mixco Viejo.

But then things changed. The Spanish found a secret passage that led into the city from a cave some distance away. The people of Mixco Viejo knew of the passage, but had seen no need to defend it because it was small and well hidden. The invaders surprised the city's inhabitants from the inside and destroyed the fortified city. (Liahona, August 2009, 22-24.)

The plot of Mixco Viejo is prefaced in the story of the Trojan horse, part of the mythological tale of the fall of the ancient city of Troy recounted in The Aeneid, written by the Roman poet Virgil.

According to the poem, after a fruitless 10-year siege of Troy, the Greeks built a huge figure of a horse. A select force of warriors hid inside the giant wooden horse. The Greeks then pretended to sail away, and the Trojans pulled the horse into their city as a victory trophy. But that night, the Greek force crept out of the horse and opened the gates for the rest of the Greek army, which destroyed the city of Troy and decisively ended the war.

Like the residents of Mixco Viejo and Troy we, as Church members today, must fortify our homes against attacks by evil forces. We, too, are at war and under siege.

And although each tale's setting was on different sides of the globe in different periods of time, the moral of both the legends is the same: It is not the things that we keep out of our homes that pose the greatest danger, but rather the things we let in.

Our war — unlike these two epic battles — is "between truth and error, between agency and compulsion, between the followers of Christ and those who have denied Him," said President Gordon B. Hinckley (Ensign, June 2007, 4–9).

Nephi warned of this modern-day battle, led by Satan and resulting in the destruction of good people who would not recognize evil.

"At that day shall [the devil] rage in the hearts of the children of men, and stir them up to anger against that which is good. And others will he pacify, and lull them away into carnal security, that they will say: All is well in Zion; yea, Zion prospereth, all is well — and thus the devil cheateth their souls, and leadeth them away carefully down to hell" (2 Nephi 28:20-21).

President Thomas S. Monson put it another way:

"We cannot afford to be complacent," he said. "We live in perilous times; the signs are all around us. We are acutely aware of the negative influences in our society that stalk traditional families. At times television and movies portray worldly and immoral heroes and heroines and attempt to hold up as role models some actors and actresses whose lives are anything but exemplary. Why should we follow a blind guide? Radios blare forth much denigrating music with blatant lyrics, dangerous invitations, and descriptions of almost every type of evil imaginable.

"We, as members of The Church of Jesus Christ of Latter-day Saints, must stand up to the dangers which surround us and our families" (April 2005 general conference; Ensign, May 2005, 19).

President Hinckley said men often install bars and bolts and electronic devices against thieves and molesters, while more insidious intruders — addictive substances, illegal drugs, pornography and other evils — enter our homes undetected.

"I know it is an old subject and one that has been dealt with much. But I repeat it again: Guard your homes," he cautioned (Ensign, January 2002, 2).

There is evil, he explained, all around us that can destroy us. It can be found in people and institutions that control "attractive but evil things that may challenge and weaken and destroy us. Included in these are beer and other liquors and tobacco. Those who market these products would like to enslave you into their use. There are illegal drugs of various kinds which, I am told, are relatively easy to obtain. For those who peddle them this is a multibillion-dollar industry, a giant web of evil.

"There is pornography, seductive and interesting and inviting. It has become a giant industry, producing magazines, films and other materials. It is available on the Internet and, if you allow, it will intrude into your home via your television. It is designed to take your money and lead you toward activities that utterly destroy.

"The giants who are behind these efforts are formidable and skillful. They have gained vast experience in the war they are carrying on. They would like to ensnare you."

However, he added, there is not a person in the Church who needs to succumb to any of these forces. "Victory will be yours. ... You are a child of God. You have His power within you to sustain you. You have the right to call upon God to protect you. ... Stand your ground and hold your place, and you will be triumphant. As the years pass, you will look back with satisfaction upon the battles you have won in your individual lives" (Ensign, January 2002, 2).

It is interesting to note that in the story of the Trojan horse, the priest Laoco guessed the Greeks' plot and warned the Trojans, "Timeo Danaos et dona ferentes." Translated, it means, "I fear Greeks, even those bearing gifts."

Cassandra, the soothsayer of Troy, also insisted that the horse would be the downfall of the city and its royal family, but she, too, was ignored.

The poem comes to a tragic result — the demise of Troy.

Those who lifted cautionary voices in Virgil's epic tale were products of the poet's imagination. We, however, have real voices of warning. Let's not ignore our leaders who have identified evil and instructed us to fortify our homes against it.