Ruy Lopez Opening

If black attacks the white bishop several things occur. White can recapture with the a pawn opening up the white rook to put pressure on a7. Since the white bishop is gone the pressure on the weak f7 square makes it difficult for a white attack. So a strategical battle occurs. Black has moved his knight several times to take your bishop, you become ahead in development if he proceeds with this play. Since the position can close up he may be trading a good piece away for a bad one. d3 and 0-0 might be best, the black bishop will not be able to develop on b2 because of the doubled pawns. But placing the bishop on e3 can put pressure on the a7 pawn. Work with the pressure you can apply and see if you can force some errors on your opponents side.

It's known as the Norwegian Variation.  The problem is that it's positionally suspect for Black.  He has zero development, and White gets a good position after 6.O-O! d6 7.d4 Nxb3 8.axb3.

Black has no development.

The a-file is open for the White Rook, and Black's a-pawn is very weak.

White owns the center

White is ahead in development and is already castled with a safe King.

There is nothing to like about Black's position.  Sure the White Light-Squared Bishop is a nice piece to have, but it's not the end all, be all, of the Ruy Lopez to the point that Black should spend for ever chasing it down and neglecting his position completely, nor should White be afraid to let the Bishop go in this particular case.

Also, with his Knight gone, there is little to no pressure on d4, which usually takes White a while to get in because he needs to prevent Bg4 with an h3 push, and needs to get in c3 to set it up, but here, with no knight on c6, and no knight to return to c6, like in the main line, with 9...Na5, he moves it to get in ...c5, but then the Knight usually comes back to c6, pressuring d4.  No such resource for Black here.

If I'm White and Black does this, I'm happy!

Sure, no problem.  If you have any other questions, I can try to answer them.  And just so you know, I'm not one of those that will throw out any answer to any question.  If it's on a subject I'm weak at, I leave it to the others to respond.  I feel it would be wrong and misleading for me to answer questions on say, Dragon theory or Grunfeld theory outside of high level stuff, like maybe what variations are ok for White against the Grunfeld.  Sure, I know he's got the Exchange, Russian Variation, early Bg5 lines, the Fianchetto lines, and 3.f3, known as the Anti-Grunfeld, which is often played by players that play the Saemisch King's Indian, but to actually explain White's ideas in the Exchange Variation, it would be wrong for me to answer, so when you see something by me, it's usually pretty genuine.

Good luck with the Ruy Lopez!