We are born for eternal life and are introduced into it by the church. Therefore we are to love the church as our neighbor on an even higher level [than we love our country]. The church teaches us the means that lead to eternal life and introduces us into that life. It leads us to eternal life by means of the true things in its body of teaching. It introduces us to that life through good ways to live.
This does not mean that we are to love the priesthood to a special degree or love the church on the priesthood’s account. We are to love the church’s goodness and truth, and love the priesthood on account of this goodness and truth. The priesthood only serves; it is to be honored according to its service.
We are to love the church as our neighbor on a higher level, even beyond our country, because our country initiates us into civic life but the church initiates us into spiritual life. Spiritual life is what sets us apart from a merely animal life.
What is more, our civic life is temporary. It comes to an end. Once it is over, it is the same as if it had not existed. Our spiritual life, on the other hand, is eternal, because it has no end. Spiritual life has a quality of reality therefore that civic life does not have. The difference between them is like the difference between what is finite and what is infinite– there is no ratio between them. Eternity is an infinity of time.
from True Christianity, Section 415