'Buy' in the Bible

I counsel thee to buy of me gold refined by fire, that thou mayest become rich; and white garments, that thou mayest clothe thyself, and that the shame of thy nakedness be not made manifest; and eyesalve to anoint thine eyes, that thou mayest see.

and that no man should be able to buy or to sell, save he that hath the mark, even the name of the beast or the number of his name.