Os Guinness said this quote

The question the doubter does not ask is whether faith was really useless or simply not used. What would you think of a boy who gave up learning to ride a bicycle, complaining that he hurt himself because his bicycle stopped moving so he had no choice but to fall off? If he wanted to sit comfortably while remaining stationary, he should not have chosen a bicycle but a chair. Similarly faith must be put to use, or it will become useless.

~ Os Guinness

To come to faith on the basis of experience alone is unwise, though not so foolish as to reject faith altogether because of lack of experience ... the quality of a Christian's experience depends on the quality of his faith, just as the quality of his faith depends in turn on the quality of his understanding of God's truth.

~ Os Guinness

There is no problem with the wider culture that you cannot see in the spades in the Christian Church. The rot is in us, and not simple out there. And Christians are making a great mistake by turning everything into culture wars. It's a much deeper crisis.

~ Os Guinness

We are not wise enough, pure enough, or strong enough to aim and sustain such a single motive over a lifetime. That way lies fanaticism or failure. But if the single motive is the master motivation of God's calling, the answer is yes. In any and all situations, both today and tomorrow's tomorrow, God's call to us is the unchanging and ultimate whence, what, why, and whither of our lives. Calling is a 'yes' to God that carries a 'no' to the chaos of modern demands. Calling is the key to tracing the story line of our lives and unriddling the meaning of our existence in a chaotic world.

~ Os Guinness