Albert Barnes Commentary John 16:29

"His disciples say, Lo, now speakest thou plainly, and speakest no dark saying." — John 16:29 (ASV)

Now you speak plainly. What he had said that perplexed them was what is contained in John 16:16. Compare to John 16:17-19: A little while and you will not see me, etc. This he had now explained by saying (John 16:28), Again, I leave the world, and go to the Father. In this there was no ambiguity, and they expressed themselves satisfied with this explanation.