While much visible ecumenical work takes place at an official level—like in the national and international dialogues—Unitatis Redintegratio expects all Catholics to get involved in some way or another. The decree lays down the marching orders for this new Catholic calling.
“Catholics, in their ecumenical work, must assuredly be concerned for their separated brethren, praying for them, keeping them informed about the Church, making the first approaches toward them.” (§4)
So far so good! But ecumenism is never only outwardly directed. It always requires a hard look at what’s going on at home.
“But their primary duty is to make a careful and honest appraisal of whatever needs to be done or renewed in the Catholic household itself, in order that its life may bear witness more clearly and faithfully to the teachings and institutions which have come to it from Christ through the Apostles.
“For although the Catholic Church has been endowed with all divinely revealed truth and with all means of grace, yet its members fail to live by them with all the fervor that they should, so that the radiance of the Church’s image is less clear in the eyes of our separated brethren and of the world at large, and the growth of God’s kingdom is delayed.” (§4)
Ecumenism in fact is another kind of reformation: and the fact that other Christians, and the whole world, are watching adds extra urgency to it.
“Christ summons the Church to continual reformation as she sojourns here on earth. The Church is always in need of this, in so far as she is an institution of men here on earth. Thus if, in various times and circumstances, there have been deficiencies in moral conduct or in church discipline, or even in the way that church teaching has been formulated—to be carefully distinguished from the deposit of faith itself—these can and should be set right at the opportune moment.” (§6)
Interestingly, this reformation also means freedom:
“All in the Church must preserve unity in essentials. But let all, according to the gifts they have received enjoy a proper freedom, in their various forms of spiritual life and discipline, in their different liturgical rites, and even in their theological elaborations of revealed truth. In all things let charity prevail. If they are true to this course of action, they will be giving ever better expression to the authentic catholicity and apostolicity of the Church.” (§4)
Protestants would do well to adopt these marching orders as their own!