Celibacy for the sake of the Kingdom is from the LORD | Card. Brandmüller
Update 03/07/2016:
Cf. Priests With Wives Yes, But As Brother and Sister | CHIESA site by Sandro Magister
Cf. Eunuchs for the Kingdom of Heaven. The Argument over Celibacy by Sandro Magister, ROME, May 28, 2010 | CHIESA site
Cardinal Schönborn proposes “rethinking” this obligation for the Catholic clergy. And so do other bishops. Benedict XVI, however, wants to strengthen it. In support he has the whole history of the Church, since the time of the apostles
[UPDATE 7/21/2019]
Tracing the Glorious Origins of Priestly Celibacy by Luiz Sérgio Solimeo | America Needs Fatima Blog