What is the license of that wallpaper?
That's not very clear to me.
But at the bottom of that page it says:
"GoodWP.com - HD desktop wallpapers
Download wallpaper scene, light, hands, concert for free with resolution 1920x1080 pix"
And there is no mention anywhere about any possible legal restrictions.
But if that website as a whole is trustworthy, I don't know really.