Psalm 114:5 is part of a larger poem celebrating God's power during the Exodus of the Israelites from Egypt. The verse is written in a poetic and rhetorical style, using personification to ask the sea and the Jordan River why they behaved in such a unusual way. To understand the meaning, we need to consider the historical context:

The Sea: Refers to the parting of the Red Sea (or the Sea of Reeds) during the Exodus. God miraculously parted the waters, allowing the Israelites to cross on dry ground while the pursuing Egyptian army was drowned.
The Jordan: Refers to the crossing of the Jordan River into the Promised Land. God stopped the flow of the Jordan, creating a dry path for the Israelites to cross.

So, the verse isn't literally asking a question to the sea and the Jordan River. Instead, it's a rhetorical question meant to emphasize the magnitude of God's power and the awe-inspiring nature of these miraculous events. It highlights that these natural elements, powerful in their own right, retreated and changed their course in the presence of God and His people.

Here's a breakdown of the verse's meaning:

"What was it, you sea, that you fled?": Why did you, a vast and mighty body of water, run away? What force was so overwhelming that it caused you to recede?
"You Jordan, that you turned back?": Why did you, a flowing river, reverse your course? What power was so great that it stopped your natural flow and made you go backwards?

The answer, though unstated, is clear: It was the presence and power of God that caused these extraordinary events. The verse serves to glorify God and remind the Israelites (and readers of the psalm) of His faithfulness and ability to perform miracles.

In essence, the verse is a poetic declaration of God's sovereignty over creation and His intervention on behalf of His chosen people.