The way to happiness is not complicated. Those who chant Nam-myoho-renge-kyo consistently in the realm of kosen-rufu triumph in the end. They are certain to attain a state of absolute happiness—in other words, the life state of Buddhahood. If you remember this single important point, your life will always be solid and secure.
From The Wisdom for Creating Happiness and Peace, part 2, revised edition, pp. 50-51

Daisaku Ikeda

His[Nichiren’s] message is that, though we all differ in our appearance and individual circumstances, each of us who embraces the Gohonzon, chants Nam-myoho-renge-kyo, and works for kosen-rufu can—just as we are, in our present form— shine like the majestic treasure tower of life adorned with the seven kinds of treasures. From The Wisdom for Creating Happiness and Peace, part 3, revised edition, p. 78

Daisaku Ikeda

When we cannot say thank you, our personal growth has stopped. When we are growing, we can see how wonderful others are too. When we stop growing, all we see are other people’s faults. At home, instead of trying to change your partner or your children to your liking, why not start with a simple “thank you”? From The Wisdom for Creating Happiness and Peace, part 2, revised edition, p. 67

Daisaku Ikeda