Whether the angels are sent on works of ministry?

Objections

Objection 1 : It would seem that the angels are not sent on works of ministry. For every mission is to some determinate place. But intellectual actions do not determine a place, for intellect abstracts from the "here" and "now." Since therefore the angelic actions are intellectual, it appears that the angels are not sent to perform their own actions.
Objection 2 : Further, the empyrean heaven is the place that beseems the angelic dignity. Therefore if they are sent to us in ministry, it seems that something of their dignity would be lost; which is unseemly.
Objection 3 : Further, external occupation hinders the contemplation of wisdom; hence it is said: "He that is less in action, shall receive wisdom" (Ecclus. 38:25). So if some angels are sent on external ministrations, they would seemingly be hindered from contemplation. But the whole of their beatitude consists in the contemplation of God. So if they were sent, their beatitude would be lessened; which is unfitting.
Objection 4 : Further, to minister is the part of an inferior; hence it is written (Lk. 22:27): "Which is the greater, he that sitteth at table, or he that serveth? is not he that sitteth at table?" But the angels are naturally greater than we are. Therefore they are not sent to administer to us.