"you think of me at all times" or "you always try act as I would want you to act" The Corinthians had not forgotten who Paul was or what he had taught them.
Paul speaks of the Corinthians believing what he taught them and obeying his commands as if he had given them a solid object that they were holding on to while someone tried to take it away. Alternate translation: "you believe and practice" (See: [[rc://en/ta/man/translate/figs-metaphor]])