This is the common denominator of the Sermon on the Mount: God’s will be done! The time for relativizing God’s will is past. What is required is not pious enthusiasm or pure interiority, but obedience in disposition and deed. Man himself must accept his responsibility in face of the closely approaching God. Only through resolutely, unreservedly doing God’s will does man come to share the promises of the kingdom of God. But God’s liberating demand is radical. It permits no casuistic compromise. It transcends and breaks through secular limitations and legal systems. The challenging examples of the Sermon on the Mount are just not meant to impose a legal limit, as to say: “Offer only the left cheek, go only tow miles, give merely your cloak, and that’s the limit of good fellowship.” God’s demand appeals to man’s magnanimity, it is a demand always for more. Indeed, it reaches to the absolute, the infinite, the whole. Can God be satisfied with a limited, conditional, formal obedience—related only to what is specifically commanded or forbidden? This would mean leaving out one final reality which cannot be brought under any amount of minute legal regulations and prescriptions and which nevertheless decides man’s attitude. God wants more: he lays claim not to half the will, but the whole. He demands not only external acts which can be observed and controlled, but also internal responses which cannot be controlled or checked. He demands man’s heart. he wants not only good fruits, but the good tree: not only action, but being; not something, but myself–and myself wholly and entirely.

On Being a Christian, p. 246

And, in order to be defensible, faith no more needs a guaranteed infallible knowledge at its disposal than loves does. Like all human knowledge, the knowledge of faith is also fragmentary. Only when faith remains aware of this does it remain free from arrogance, intolerance and false zeal.

On Being a Christian, p. 159

Christianity must not be confused with show business or the narcotics industry.

On Being a Christian, p. 137

It seems there are as many images of Christ as there are minds. Even today piety provides very diverse answers to the question: “Which Christ? What does he mean for me?”

On Being a Christian, p. 129

It is evident from the history of the Christian Church, of theology and spirituality, that being Christian has meant all too often being less than human.

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The Christian may indeed want to live for men, but he is often not enough of a man himself. He is very ready to save others, but he has never learned properly to swim himself.

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Is not the lack of genuine, complete humanity particularly with official representatives and exponents of the Churches the reason why being a Christian is disregarded or rejected as an authentically human possibility? Must we not strive for the best possible development of the individual: a humanization of the whole person in all his dimensions, including instinct and feeling? Being human ought to be complementary to being a Christian. The Christian factor must be made effective, not at the expense of the human, but for the benefit of the latter.

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