Exodus 16:14-15
And when the dew had gone up, there was on the face of the wilderness a fine, flake-like thing, fine as hoarfrost on the ground. When the people of Israel saw it, they said to one another, "What is it?" For they did not know what it was. And Moses said to them, "It is the bread which the LORD has given you to eat."
The ancient Israelites were fed by miraculous food in the wilderness of Sinai. It was yummy, but the natural question they asked was "What is it?" Some may have had their doubts about nibbling it at first but, as the Yiddish saying goes, "Hunger is the best sauce" and they soon were all eating with a will. But they never did figure out what it was. Indeed, the name they gave it — manna — basically means "Whatsit" in English. Novelist Frank Schaeffer, a member of the Orthodox communion, relates a moment in his catechesis when he confronted his priest and asked why they gave Eucharist to infants in the Eastern Church. "After all," he remarked, "they don't even know what it is!" His priest turned to him with an eyebrow arched and replied, "Do you?" In the face of a true miracle it's better to receive first and analyse later. If the analysis of manna or Eucharist turns up nothing, that doesn't mean it can't still satisfy your hunger, whether of body or soul.