It arises from a saying of Christ. There are, Christ says, those who give up marriage for the sake of the kingdom of heaven and bear testimony to the kingdom of heaven with their whole existence. Very early on the Church came to the conviction that to be a priest means to give this testimony to the kingdom of heaven. In this regard, it could fall back analogously to an Old Testament parallel of another nature. Israel marches into the land. Each of the eleven tribes gets its land, its territory. Only the tribe of Levi, the priestly tribe, doesn’t get an inheritance; its inheritance is God alone. This means in practical terms that its members live on the cult offerings and not, like the other tribes, from the cultivation of land. The essential point is that they have no property. In Psalm 16 we read, You are my assigned portion; I have drawn you as my lot; God is my land. This figure, that is, the fact that in the Old Testament the priestly tribe is landless and, as it were, lives on God — and thereby also really bears witness to him — was later translated, on the basis of Jesus’ words, to this: The land where the priest lives is God.
We have such difficulty understanding this renunciation today because the relationship to marriage and children has clearly shifted. To have to die without children was once synonymous with a useless life: the echoes of my own life die away, and I am completely dead. If I have children, then I continue to live in them; it’s a sort of immortality through posterity. For this reason the ultimate condition of life is to have posterity and thereby to remain in the land of the living.
The renunciation of marriage and family is thus to be understood in terms of this vision: I renounce what, humanly speaking, is not only the most normal but also the most important thing. I forego bringing forth further life on the tree of life, and I live in the faith that my land is really God — and so I make it easier for others, also, to believe that there is a kingdom of heaven. I bear witness to Jesus Christ, to the gospel, not only with words, but also with this specific mode of existence, and I place my life in this form at his disposal.
In this sense, celibacy has a Christological and an apostolic meaning at the same time. The point is not simply to save time — so I then have a little bit more time at my disposal because I am not a father of a family. That would be too primitive and pragmatic a way to see things. The point is really an existence that stakes everything on God and leaves out precisely the one thing that normally makes a human existence fulfilled with a promising future.
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The poorer an age is in faith, the more frequent the falls. This robs celibacy of its credibility and obscures the real point of it. People need to get straight in their minds that times of crisis for celibacy are always times of crisis for marriage as well. For, as a matter of fact, today we are experiencing not only violations of celibacy; marriage itself is becoming increasingly fragile as the basis of our society. In the legislation of Western nations we see how it is increasingly placed on the same level as other forms and is thereby largely “dissolved” as a legal form. Nor is the hard work needed really to live marriage negligible. Put in practical terms, after the abolition of celibacy we would only have a different kind of problem with divorced priests. That is not unknown in the Protestant Churches. In this sense, we see, of course, that the lofty forms of human existence involve great risks. – from Salt of the Earth (1997)