here in Matthew chapter 19 Jesus tells a man the commandments he has to do to gain life... which apparently did not include partaking of his flesh and blood. so this means that this man could have everlasting life and not partake of the emblems. they knew not of them.
16 Just then a man came up to Jesus and asked, “Teacher, what good thing must I do to get eternal life?”
17 “Why do you ask me about what is good?” Jesus replied. “There is only One who is good. If you want to enter life, keep the commandments.”
18 “Which ones?” he inquired.
Jesus replied, “‘You shall not murder, you shall not commit adultery, you shall not steal, you shall not give false testimony, 19 honor your father and mother,’[c] and ‘love your neighbor as yourself.’[d]”now surely if there were more, Jesus would have said so right?