By eternity, Lynn meant that we are perpetually in the present. Think of it as the exact opposite of your belief that all we have is measurable past and promise of future. In reality, all we have is right now. The future doesn't exist except in our minds, and the past is nothing but bygone "nows." It is only in our cultural beliefs that the past and future are what matter...we stare backward at one, and focus intently on the other, not realizing that we are ignoring the only thing that is real...the present.