What is “safe eating”?

Hello Rabbi,
In the Bible, Rabbah 2:2 it is stated as follows:
In the Sinai Desert (Numbers 3:4), and that in the Sinai Desert they died, but it teaches that Mount Sinai they took their own apoplexy to die, as it is written (Exodus 24:11): And he did not lay his hand on the nobles of the children of Israel, said Rabbi Pinchas, hence they were worthy of laying hands on. Rabbi Hoshaya said, and that Kilorin went up with them to Sinai, how many times (Exodus 24:11): And they saw God and ate and drank, but it teaches that their eyes were adulterous towards the Divine Presence, as a man looks at his companion while eating and drinking. Rabbi Yochanan said, Eating is certain , as it is written (Proverbs 16:15): In the light of the face of the king of life.
What is meant by the phrase “certain eating” according to Rabbi Yochanan?
Best regards,