The Seventh Ecumenical Council.  The Second Council of Nice 24Canon XV.

That a clerk ought not to be set over two churches.

From henceforth no clergyman shall be appointed over two churches, for this savours of merchandise and filthy lucre, and is altogether alien from ecclesiastical custom. We have heard by the very voice of the Lord that, "No man can serve two masters, for either he will hate the one and love the other, or else he will hold to the one and despise the other." Each one, therefore, as says the Apostle, in the calling wherein he was called, in the same he ought to abide, and in one only church to give attendance. For in the affairs of the Church, what is gained through filthy lucre is altogether separate from God. To meet the necessities of this life, there are various occupations, by means of which, if one so desire, let him procure the things needful for the body. For says the Apostle, "These hands have ministered unto my necessities, and to them that were with me." Occupations of this sort may be obtained in the God-protected city. But in the country places outside, because of the small number of people, let a dispensation be granted.