Ever since attendance at Mass on major feast days had seriously declined, parishes like the one I belong to have begun celebrating those major feasts on the Sunday "within the Octave," that is, during the eight day period of the feast and the seven following days. That means this Sunday for our parish is the observance of the feast of St. Michael the Archangel and All Angels.
What we think we know about angels today is a hodgepodge of speculation over the centuries, drafted by Jewish mystical speculation, Catholic speculation (based on hints within pre-Christian Jewish tradition, hints in Scripture, testimony from the lives of the Saints, and heavy application of Aristotelian metaphysical principles), and other more fanciful ideas spurred on by cultural sentimentality or even mind-altering substances.
In other words, not much.
The fact that Scripture is peppered with references to them, that our Lord had regular dealings with them. More often than not, people were either unaware the person speaking to them was an angel (the three angels appearing to Abraham and Sarah at Mamre, or the angel appearing to Manoah and his wife, or the angel Raphael travelling with Tobias), or scared almost witless and requiring reassurance (Isaiah, Ezekiel, the Virgin Mary). Our ideas of androgynous or even feminine beings with wings are merely the misapplication of the metaphors of the iconography of late Antiquity/the early Middle Ages.
For the feast day, the Epistle is drawn from the Revelation to St. John the Divine, (Rev. 12.7-12) a very controversial book from Scriptural canon. It speaks of war in the heavenly dimension, where angels battle and where the angels under the leadership of Michael ("He who is like God") casts out the Dragon (a/k/a the Devil (the Accuser) and Satan (the Adversary)) and his angels from that dimension into ours. Not a Hell dimension, but ours. In fact, the Book of Revelation does not land Satan in the dimension of the Abyss (not Hell, which is the place of the dead) until much later, and that at the hand of an unnamed angel. (Rev. 20.2-3).
What this says is that angels are not all of a piece. Some are for God, some are not, some are our friends, some are decidedly not (very decidedly not), and that they are all over the place within our dimension, but not visible because they really don't belong in it. God's angels belong in the heavenly dimension unless they are on assignment, whereas the Devil and his angels are here on sufferance.
That being said, what we should take from this is that angels' business is not our business unless their business is a specific assignment from God. While we may seek their prayers before the throne of God, we should not be seeking association or summoning them, for either they will be fully obedient to God and come only when He assigns the, or they are among the disobedient and ultimately mean us ill. This is not a good area for experimentation. Those who mean us well are completely dedicated to God, and thereby worthy of respect and veneration, but not worship, for they are fellow servants of God with us. (Rev. 19.10)
So angels are among us every so often, and like us are fellow servants of God. At least some of them are. So let us honour those who without a moment's pause continually serve the Lord our God and let us give thanks for that ministry, largely unseen by us.
Christ the Ruler of All (Christos Pantokrator) Surrounded by Angels, Capella Palatina, Palermo, Sicily, 12th Century A.D.