What do you mean by that? I say "I understand the desire to have an unmarried clergy" because the unmarried person can focus on serving God (as Paul discusses in 1 Corinthians 7.) However I don't see how forced celibacy of clergy can be reconciled with 1 Timothy 3 or Titus 1, where God, via Paul, explicitly permits several levels of church leadership to be married. Both passages discuss the office of an elder or bishop, who are "the husband of one wife" as the Douay-Rheims expresses it, and who may have children. Sexual purity is clearly an important qualification, but it would seem that it can be purity through celibacy or through right conduct in a married relationship (since the holder of this office may have children). Per 1 Cor. 7:5 it could be said that sexual intercourse within the marital relationship would be permitted to holders of this high office within the church.
"Then Peter said: Behold, we have left all things and have followed thee. Who said to them: Amen, I say to you, there is no man that hath left home or parents or brethren or wife or children, for the kingdom of God's sake, Who shall not receive much more in this present time, and in the world to come life everlasting." Luke 18:28-30
We know Peter was married at some point. Jesus healed his wife's mother in Matt 8:14. Clement of Alexandria, who died in 215 AD or thereabouts, seems to interpret 1 Cor. 9:5 as I do in his Stromata (see sections 52, 53). He even takes it farther than I (I think it's pretty clear scripturally that Paul was, in fact, celibate.) Clement also teaches that Peter's wife was martyred. Also in 1 Cor. 7:10,11 Paul teaches as a command from the Lord that marriages were not to be broken. To dissolve one's marriage to serve Christ would be wrong, wouldn't it?
The discipline of celibacy and the priesthood in the Catholic Church has its origin with the Apostles and finds its genesis with Melchisedech in the Levitical priesthood in the Old Testament.
Were not the priests, even the high priest, permitted to marry (Leviticus 21)?
They were married, but required to live continently when they were actually serving the Temple. Marital intercourse rendered one ritually impure for a day (Lev 15:18) and would therefore have been incompatible with Temple service. See also this interesting article which has some information on celibacy in Jewish tradition.