For many people, they are just being observant.
I also suspect there might be some spiritual perception occurring when people remark with that phrase. In other words, the comment might manifest not so much the soulish expression of recall, but a spiritual perception of its association giving rise to a thought in the person in fellowship with God through faith in Christ. We might not be focusing on who originated the thought in us, but simply recognize the spiritual perception. Nothing clever is being suggested.
Some observers are immune to some observations.
Or blind or some such.