I think it has to do with the fact that water moves and so is never in the same place for very long. So, ... the next time a ship sails on that sea the water they sailed on the first time moved on (as they themselves did) and there is "different" water there the next time they arrived.
The word for saying the same thing twice is "redundancy."
meaning: "not twice for the same".
Twice in Math would mean the same as it would anywhere elses. It would mean to do something two times.
If you mean for the same judgment, YES. Two judgments for the same defaulted loan, NO.
Savior of life
'Tis himself is the same as saying "It's him."
The dream suggests that you need to mend your relationship with this person. Dreaming of hurting the same person twice emphasizes the importance of reconciliation.
the person can not be tried for the same crime twice.
It usually means that the same chance occurrence cannot happen twice.
Bi-weekly is ambiguous, and can either mean twice a week, or once every two weeks.
This isn't an idiom because it means exactly what it says. It is an old saying or proverb. Lightning doesn't seem to strike twice in any one spot, so people say that when they hope that something horrible isn't going to happen again.
The saying "lightning never strikes twice in the same place" is a commonly held belief, but it is not a scientific theory. In reality, lightning can and does strike the same location multiple times, especially tall structures like skyscrapers and towers.