Having non-married priests is not a simple (human) praiseworthy tradition or a mere discipline. Priests must be as close as possible to our Lord Jesus Christ's perfection.
God wants all His ministers to be chaste, completely pure, and holy. This is the Divine Will of the Eternal Father. Whether they are bishops, priests, deacons, acolytes etc. There is no exception, everything else is only the result of human errors and of the actions of Satan in the Church. Chastity is compulsory for priests and other ministers, all men or boys who must serve God near His altars in His sanctuaries (the space after the communion table up to the apse). To be chaste, one must, among other things, put oneself in a situation that is most conducive to chastity. To do this one must obviously not get married.
Therefore, upheavals of history can not be invoked to justify married clergy, and especially not eastern practices. In the east, they knew that bishops and priests should be chaste, but they wrongfully looked at the Mosaic Law and decided that priests should be chaste only one day a week, the day of the Sacrifice of the Mass, and then, the appropriate conduct of treating their wives as sisters was gone! To go from bad to worse, they began to say Holy Mass more often without new days of mandatory abstinence.
Even before God decreed the definitive and perfect covenant through the person of the Son of God. There was the imperfect covenant of preparation that announced the New Testament. In this ancient covenant, priests had to be temporarily chaste to serve God in His Temple. They had to abstain from all conjugal relationships and to live in a house without the presence of their wives. Priests of the Mosaic Law were not always active. There was a system of rotation, and their priestly function was not as sacred as in the New Testament's priesthood.
Pope Pius XII,
Sacra Virginitas §23:
Consider again that sacred ministers do not renounce marriage solely on account of their apostolic ministry, but also by reason of their service at the altar. For, if even the priests of the Old Testament had to abstain from the use of marriage during the period of their service in the Temple, for fear of being declared impure by the Law just as other men, is it not much more fitting that the ministers of Jesus Christ, who offer every day the Eucharistic Sacrifice, possess perfect chastity? St. Peter Damian, exhorting priests to perfect continence, asks: "If Our Redeemer so loved the flower of unimpaired modesty that not only was He born from a virginal womb, but was also cared for by a virgin nurse even when He was still an infant crying in the cradle, by whom, I ask, does He wish His body to be handled now that He reigns, limitless, in heaven?"@Urget Nos @John A Cassani @Orthocat