I refer to the article in the October AD2000 (page 13) by Fr Thaddeus Doyle, reprinted from The Irish Catholic.
Fr Doyle maintains there was a rule in the early Church that as soon as married men were ordained "they were expected to renounce the use of their marriage and to live as brother and sister with their wives".
He says that the Council of Elvira in Spain, at the beginning of the fourth century, enacted that clerics "must live in abstinence with their wives". But he does not say that the subject came up at the much more important First Ecumenical Council of Nicaea in 325.
The Catholic Encyclopaedia says: "It seems that most of the bishops present [at Nicaea] were disposed to follow the precedent of the Council of Elvira prohibiting conjugal relations to those bishops, priests, deacons and sub-deacons, who were married before ordination. Paphnutius earnestly entreated his fellow-bishops not to impose this obligation on the orders of the clergy concerned.
"He proposed that only those who were celibates at the time of ordination should continue to observe continence, but, on the other hand, that 'none should be separated from her, to whom, while yet unordained, he had been united'.
"The great veneration in which he was held, and the well known fact that he had himself observed the strictest chastity all his life, gave weight to his proposal, which was unanimously adopted. The Council left it to the discretion of the married clergy to continue or discontinue their marital relations."
Paphnutius said that his proposal was "in accordance with the ancient tradition of the Church", and none of the other bishops there contradicted him.
So I do not see how Fr Doyle can claim that the rule he quotes goes back to the Apostles.