Contradiction with Exodus 13:21
Exodus 13:21 describes God leading the Israelites with a pillar of cloud by day and a pillar of fire by night, consistent with Psalms 78:14, and thus does not directly contradict it.
Exodus 13:21: And the LORD went before them by day in a pillar of a cloud, to lead them the way; and by night in a pillar of fire, to give them light; to go by day and night:
Paradox #1
The potential contradiction is that guiding people with a pillar of cloud by day and a pillar of fire by night involves supernatural phenomena that do not align with scientific understanding of meteorological or natural light occurrences. In science, clouds and fire are explained through natural processes that do not change their nature to guide people.