Albert Barnes Commentary Psalms 114:5-6

"What aileth thee, O thou sea, that thou fleest? Thou Jordan, that thou turnest back? Ye mountains, that ye skip like rams; Ye little hills, like lambs?" — Psalms 114:5-6 (ASV)

What ailed you, O you sea, that you fled?... - literally, “What to you, O you sea,” etc. That is, What influenced you - what alarmed you - what put you into such fear, and caused such consternation? Instead of stating the cause or reason why they were so thrown into dismay, the psalmist uses the language of surprise, as if these inanimate objects had been struck with sudden terror, and as if it were proper to ask an explanation from them regarding conduct that seemed so strange.