This is soooo achingly beautiful. I may be alone in liking both versions equally - the sudden, lightning-flash illumination of the other is very effective too. When I first saw the title I was puzzled, thinking it referred to 'Severus ... please ...' After studying this brilliant piece, the two moments are forever counterpoised for me.
Wow, what a powerful and iconic image. I agree with *joeyv7, Snape almost looks like he is falling back in terror and humility before some avenging god. Effective and appropriate, I think, considering the scene you are portraying here.
Incredibly convincing and insightful - I feel the power and and helpless terror of the figures. The composition is really effective; the light and symbols around the wands are iconic and so *right*. Devastating. I wish I could do as well as this.
There is also something very striking in the contrast between them - the white robe / the black robe, the elder man / the youth on Snape body and face, the powerful move of Albus and this defeated and surrending posture for Severus.
This scene in the book shows precisely this... How much Severus is displaying a lot of courage and humility, facing someone who holds his life and his hope in the tip of his wand. And this pictures conveys it very well.
You're right. There is something iconic in their characters indeed - Albus is powerful, wise and omniscient, trust or misunderstood but acting for the best, he as the function of God for the others, even if he is by himself walking on his personal path and would eventually fall by his own. The picture reminds of these icons of an avenging God punishing the falling sinner.
If there is one character in these series who needs to kneel down for a God, then it's Severus for sure