Directing his Saturday afternoon address to children and youth, President Boyd K. Packer spoke of how his brother, a much-decorated B-24 pilot during World War II, had taught him about the power of prayer and the important role of sacred music.

His brother Leon, who went on to become a brigadier general in the Air Force, had narrowly escaped death several times while in the armed services. President Packer, acting president of the Quorum of the Twelve, said that when he was a 20-year-old pilot about to go to war, he spent a few days with his brother. "Leon told me how he was able to hold himself together under fire," President Packer related. "He said, 'I have a favorite hymn . . . and when things got rough I would sing it silently to myself, and then there would come a faith and assurance which kept me on course.' "

President Packer spoke of one of his own narrow escapes while serving in Japan when his crew's plane was lost, the radio was out and they were caught in a typhoon. He said, "In that desperate situation, I remembered the words of my brother. I learned that you can pray and even sing without making a sound. I had experienced the power in prayer and in sacred music. I learned that both can be very private and very silent.

"While that experience was dramatic, the greater value of Leon's lesson came later in everyday life when I faced the same temptations that you face now. As the years passed, I found that, while not easy, I could control my thoughts if I made a place for them to go. You can replace thoughts of temptation, anger, disappointment, or fear with better thoughts — with music."

He said that hymns of the Restoration carry inspiration and protection. He admonished children and youth to leave alone music that is spiritually destructive, bad and dangerous.

"Thoughts are talks we hold with ourselves," President Packer said. "Do you see why the scriptures tell us to 'let virtue garnish thy thoughts unceasingly,' and promise us that if we do, . . . 'the Holy Ghost shall be [our] constant companion'?" (D&C 121:45-46.)

President Packer explained, "The voice of the Spirit is felt rather than heard. You can learn when you are very young how the Holy Ghost works.

"The scriptures are full of help on how good can influence your mind and evil control you, if you let it. That struggle will never end. But remember this," he said, quoting an anonymous poet: " 'All the water in the world, However hard it tried, Could never sink the smallest ship unless it gets inside. And all the evil in the world, The blackest kind of sin, Can never hurt you the least bit Unless you let it in.' "

He added: "When you learn to control your thoughts, you will be safe."

Further, he admonished: "Young Latter-day Saints, shape up! Face up! Take hold of your lives! Take control of your mind, your thoughts! If you have friends who are not a good influence, make changes, even if you face loneliness, even rejection.

"If you have already made bad mistakes, there are ways to fix things and eventually it will be as though they never happened.

"Sometimes guilt controls our thoughts and takes us prisoner in our mind. How foolish to remain there when the door stands open. Don't tell yourself that sin doesn't really matter. That won't help; repentance will."