Prayer: the key of the day and the lock of the night.
Physical fitness is not only one of the most important keys to a healthy body, it is the basis of dynamic and creative intellectual activity.
Who knows the mind has the key to all things else.
Education is the key to unlocking the world, a passport to freedom.
Imagination is the key to my lyrics. The rest is painted with a little science fiction.
Prayer is the key of the morning and the bolt of the evening.
Simplicity is the key of elegance.
Simplicity is the key to brilliance.