1Sa 28:13 And the king said unto her, Be not afraid: for what sawest thou? And the woman said unto Saul, I saw
gods ascending out of the earth.
1Sa 28:14 And he said unto her,
What form is he of?
[what does he look like] And she said, An old man cometh up; and he is covered with a mantle. And Saul perceived that it was Samuel, and he stooped with his face to the ground, and bowed himself.
So what were these 'gods' that the woman saw and Saul asked what
one of these gods, that she said was Samuel, look like?
"There appears much solemnity in God's permitting the soul of a departed prophet to come as a witness from heaven, to confirm the word he had spoken on earth." Matthew Henry
http://biblehub.com/commentaries/mhc/1_samuel/28.htm
"5. I believe that the woman of En-dor had no power over Samuel; and that no incantation can avail over any departed saint of God, nor indeed over any human disembodied spirit.
6. I believe Samuel did actually appear to Saul; and that he was sent by the especial mercy of God to warn this infatuated king of his approaching death, that he might have an opportunity to make his peace with his Maker.
7. I believe that the woman found, from the appearances, that her real or pretended charms had no effect; and that what now took place came from a totally different disposition of things from those with which she was conversant.
8. I believe that direct, circumstantial, and unequivocal oracles were now delivered concerning things which neither human nor diabolical wisdom could foresee or penetrate; that the defeat of the Israelites, and the death of Saul and his three sons on the following day, were matters which, from their nature, could only be known to God himself; and that no demon or bad spirit could be employed in such a transaction." Adam Clarke
http://biblehub.com/commentaries/clarke/1_samuel/28.htm