If the Catholic church never adopted celibacy for priests, retaining it only for certain monastic orders, it would likely take a fair bit out of the fire for Reformation. This is because saying that priests must be celibate is precisely contrary to Scripture. It's not a case of wiggle room or interpretation, it is black and white.
Specifically, for those that care about such things
1 Timothy 3:2-12 King James Version (KJV)
2 A bishop then must be blameless, the husband of one wife, vigilant, sober, of good behaviour, given to hospitality, apt to teach;
3 Not given to wine, no striker, not greedy of filthy lucre; but patient, not a brawler, not covetous;
4 One that ruleth well his own house, having his children in subjection with all gravity;
5 (For if a man know not how to rule his own house, how shall he take care of the church of God?)
6 Not a novice, lest being lifted up with pride he fall into the condemnation of the devil.
7 Moreover he must have a good report of them which are without; lest he fall into reproach and the snare of the devil.
8 Likewise must the deacons be grave, not doubletongued, not given to much wine, not greedy of filthy lucre;
9 Holding the mystery of the faith in a pure conscience.
10 And let these also first be proved; then let them use the office of a deacon, being found blameless.
11 Even so must their wives be grave, not slanderers, sober, faithful in all things.
12 Let the deacons be the husbands of one wife, ruling their children and their own houses well.
Note that it says the bishop must be the husband of one wife, and he's expected to handle his own household and children well. This means not only MAY he be married, he MUST be.
What's more, this statement is made by Paul, who is...drumroll...himself a celibate. So he's laying out the qualifications for an office that he doesn't meet. He's more a monastic/mystic and this admission against interest shows that clearly he's supposed to 'stay in his lane'.