The starting premise--celibacy is not essential to the priesthood--is surely something everyone agrees upon. Jesus explicitly chose married men as his apostles. Peter, a married man, was Jesus' handpicked leader. The epistles clearly contain references to married bishops and priests. For the first 12 centuries of church practice, 39 popes were married, in addition to many priests and bishops. Three popes (Anastasius I, Saint Hormidas, and Sergius III) produced pope sons of their own, two of whom went on to be declared saints (Saint Innocent I and Saint Silverius).
But in the 11th century, the starting premise was mothballed. Pope Gregory VII mandated that anyone seeking ordination must first pledge celibacy, stating that "the church cannot escape from the clutches of the laity unless priests first escape the clutches of their wives." The Second Lateran Council and Pope Innocent II (forgetting the example of his fifth-century namesake) effectively put a halt to the married priesthood in 1139.
The starting premise was chained up for centuries until June 1980, when John Paul II fiddled with the lock. He made special pastoral provisions for married Protestant ministers who converted to Catholicism to be ordained to the Catholic priesthood, bringing along their wives and children--provision that, to this day, most U.S. Catholics are unaware of.
Since then, 70 Episcopalians and an assortment of Lutheran, Methodist, and Presbyterian clerics--most of them married--have converted to Catholicism and been ordained Catholic priests in the United States. The practice continues worldwide.
In roughly that same time frame, 23,000 U.S. Catholic priests have left active ministry (100,000 worldwide). Twenty-five percent of the world's parishes are now said to be without resident priests.
So how can we start from the same premise--celibacy is not essential to the priesthood--and end up with such different conclusions concerning formerly Protestant married priests and Catholic priests who resigned and then married?
This is the way the Vatican sees it for married Protestant ministers who have converted to Catholicism and are now practicing, married Catholic priests: Becoming a Catholic priest should not require these clergy to forsake the marriage commitment made prior to becoming Catholic. The original promise of these priests--to be Anglican and to minister to Anglican congregations--can be renegotiated without it affecting their status as an active Catholic priest.
And this is the way the Vatican sees it for celibate Catholic priests: Becoming a Catholic priest requires forever forsaking a marriage commitment. Original promises by the celibate Catholic priests--to be celibate while being a Catholic priest--cannot be renegotiated without their active status as Catholic priests ending.
Why not welcome married Catholic priests back to active Catholic ministry the way we welcome recently converted married Protestant clergy? Church leaders assert that there are two major obstacles to this. First, they say that the Catholic who leaves the ministry in order to marry is in a significantly different situation from the married priest convert. The Catholic candidate, prior to his ordination as a priest, agrees to celibacy as a standard set by the church in 1139 for all priests ordained in the Latin Church. But this does not bind the convert. His denomination permitted him to be both married and a minister. He did not promise to be celibate. Being received as a Catholic priest, therefore, should not require forsaking his freely chosen marriage commitment.
Second, it is simply not fair, the church says, to allow for the reentry of inactive married Catholic priests. Laymen who have chosen not to be priests and are now married would howl. Active celibate priests who have lived the long, solitary promise would howl. Seminarians who have not pursued or who have cut off promising romantic relationships would howl. People in the pews would howl because the Father who left to become a Mister is back as a Father Mister.
The fact of the matter is that most priests struggle with celibacy--a human-made requirement for ordination. They live with a prerequisite that must be complied with in order to get to their real call, which is to be a priest. Candidates to the priesthood desire with all their hearts to be priests. They pray with all their hearts that something might help them live out the celibacy cover charge in a relatively healthy and life-giving fashion.