He did in certain and distinct terms in verse 63:
"It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, they are spirit, and they are life"
In other words, "eat my flesh and drink my blood, but you'll find that it's a waste of your time".
I don't think so. "These words", i.e., the words that I have just spoken to you, are spirit and life. 6:63 intensifies the previous chapter, it doesn't negate it.