415. And I looked, and I heard an angel flying in the midst of heaven. (8:13) This symbolizes instruction and prediction from the Lord.

In the highest sense an angel means the Lord, and so also something from the Lord (no. 344). And to fly in the midst of heaven and speak means, symbolically, to perceive and understand, and when said of the Lord, to foresee and provide (no. 245). But here it means to instruct and predict.

123. That ye may be tried, signifies consequent increase of longing for truth. This is evident from the signification of "being tried," as being to be infested by falsities (of which see in The Doctrine of the New Jerusalem 197, 198). But here, since it is said, "the devil shall cast some of you into prison," by which such infestation is meant, so "being tried" signifies increase of longing, and as a consequence, increase of truth, since temptations effect this. (That through the temptations in which man conquers there come illustration and perception of truth and good, see Arcana Coelestia 8367, 8370; that intelligence and wisdom are therefrom, n. 8966, 8967; that truths increase immensely after temptations, n. 6663; with many other things that may be seen in The Doctrine of the New Jerusalem 187-201.)