I downloaded a resource pack. I did it right because it's worked before I went on Minecraft chose the resource pack but while loading it crashed.

What I expected to happen was it to load and have played with a different texture.

What actually happened was while loading the texture pack/resource pack Minecraft crashed.

1.Download the PureBDcraft 512xMC18 resource pack/texture pack on Mac Minecraft 1.8.9.
2.Put it in resource pack folder and open the .zip and open Minecraft 1.8.8 (no snapshots).
3.Play Minecraft go on resource pack select the resource pack PureBDcraft and then press done and then it crashed for me. I did try opening Minecraft but it crashed again.