Rembrandt:the angel leaves Tobit and his family

At the conclusion of a treacherous journey, the angel has accomplished his mission and leaves the family. Wikipedia has a good summary of the story.

St Michael

This image of St Michael trampling the dragon comes from the Sforza Book of Hours. Sforza Hours at the British Library

St Michael,
glorious Prince,
Chief and Champion of the Heavenly Host,
our worthy leader,
endowed with superhuman excellence and virtue:
free us from every ill,
who with full confidence have recourse to thee;
and by thine incomparable protection
enable us to make progress every day
in the faithful service of our God.
Amen.

Elijah and an Angel

In this painting, Juan Antonio de Frías y Escalante (1633-1669) shows an angel coming to Elijah, a story related in I Kings 19:4-8:

...he himself went a day's journey into the wilderness, and came and sat down under a juniper tree: and he requested for himself that he might die; and said, It is enough; now, O LORD, take away my life; for I am not better than my fathers.

And as he lay and slept under a juniper tree, behold, then an angel touched him, and said unto him, Arise and eat.

And he looked, and, behold, there was a cake baken on the coals, and a cruse of water at his head. And he did eat and drink, and laid him down again.

And the angel of the LORD came again the second time, and touched him, and said, Arise and eat; because the journey is too great for thee.

And he arose, and did eat and drink, and went in the strength of that meat forty days and forty nights unto Horeb the mount of God.

Three Visitors

Gustav Doré (1832-1883) imagined that Abraham encountered the Three Visitors from afar, a contrast to the views shown by Chagall and by Rublev's icon.

The story is found in Genesis 18, 1-16.

The Vision

"The Vision" by Marc Chagall (1887-1985) brings to mind these lines of John Milton's (1608-1674) from Paradise Lost:

Millions of spiritual creatures walk the earth
Unseen, both when we wake and when we sleep.