Modern thinking usually lets itself be guided by the idea that eternity is imprisoned, so to speak, in its unchangeableness; God appears as the prisoner of his eternal plan conceived “before all ages”. “Being” and “becoming” do not mingle. Eternity is thus understood in a purely negative sense as timelessness, as the opposite to time, as something that cannot make its influence felt in time for the simple reason that it would therefore cease to be unchangeable and itself become temporal. Fundamentally these ideas remain the products of a pre-Christian mentality which takes no account of a concept of God that finds utterance in a belief in creation and incarnation
But eternity is not the very ancient, which existed before time began, but the quite other, which is related to every passing age as its today, and is really contemporary with it; it is not itself barred off into a “before” and “after”; it is much rather the power of the present in all time. Eternity does not stand by the side of time, quite unrelated to it; it is the creatively supporting power of all time, embracing passing time in its own present and thus giving it the ability to be. It is not timelessness but control of time. As the present that is contemporary with all ages it can also make its influence felt in any age.
The incarnation of God in Jesus Christ, by virtue of which the eternal God and temporal man meet in one single person, is nothing else than the last concrete manifestation of God’s control of time. At this point of Jesus’ human existence God took hold of time and drew it into himself. His power over time stands embodied before us, as it were, in Christ. Christ is really, as St John’s gospel says, the “door” between God and man (John 10.9), the “mediator” (1 Tim 2.5), in whom the Eternal One has time. In Jesus we temporal beings can speak to the temporal one, our contemporary; but in him, who with us is time, we simultaneously make contact with the Eternal One, because with us Jesus is time and with God eternity.
In his earthly life Jesus did not stand above time and space but lived from the midst of his time and in time. The humanity of Jesus, which placed him in the midst of that age, hits us in every line of the gospels; and we have, from many points of view, a clearer and more living picture of him than was vouchsafed to earlier periods. But this “standing in time” is not just an outward cultural and historical framework, behind which could be found somewhere ot other, untouched by it, the supratemporal essence of his real being; it is much rather an anthropological state of affairs, which profoundly affects the form of human existence itself.
Jesus has time and does not anticipate in sinful impatience the will of the Father. “Therefore the Son, who in the world has time for God, is the original place where God has time for the world. God has no other time for the world than in his Son; but in him he has all time” (Urs von Balthasar). God is not the prisoner of his eternity: in Jesus he has time – for us, and Jesus is thus in actual fact the “throne of grace” to which at any time we can “draw near with confidence” (Heb 4.16).