Why is Pawn on B4 important?

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Avatar of metaxzen

I'm watching an Openings for Beginners video http://www.chess.com/video/player/openings-for-beginners-the-old-indian-defense and FM Lilov is talking about the importance of white getting his pawn to B4.

I'm curious, why is that crucial? 

 

Thank you!

Avatar of Scottrf

Which lines?

Maybe just to gain space? Hard to say without knowing exactly where he wants you to play b4.

Avatar of dgmisal
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Avatar of metaxzen

The video is about the old indian defense, the standard variation.