1/4/19 Burn one’s bridges and burn one’s boats

The idioms burn one’s bridges and burn one’s boats means to do something that is not easily undone, to do something that makes returning to one’s original state an impossible task. Most often, the idioms to burn one’s bridges and to burn one’s boats are used in the negative sense, as in don’t burn your bridges or don’t burn your boats. These are admonitions that are meant to discourage someone from leaving a situation in an irredeemable manner. For instance, if someone quits a job by hurling an insulting tirade at his boss, not only will he not be rehired, he will not receive a favorable reference from that person. That person is said to have burned his bridges with his last employer.
The terms burn one’s bridges and burn one’s boats have their origins in ancient Rome, though these phrases did not come into common use until the 1800s. Like many idioms, these phrases have a literal origin. It was a practice in Roman warfare to destroy bridges. Sometimes, these bridges were destroyed in order to stop the enemy from fleeing. Other times, the bridges were destroyed behind the Roman armies in order to leave no way to retreat. This meant that the armies had to fight to the death, or to victory.
In the same manner, ancient navies might destroy their boats upon landing on the enemies’ shore. By burning or otherwise sinking their fleet, ancient soldiers and sailors could not retreat. They had no choice but victory. Of course, the vessels were only destroyed after everyone on board had debarked. While referencing ancient military tactics, the idioms burn one’s bridges and burn one’s boats came into general usage in the 1800s.
Note that the word one’s is spelled with an apostrophe, as it is possessive.
While the adage “don’t burn your bridges” is most often applied to departing employees, the same holds true for the employers seeing them go.
You burn a bridge when you break up with your sweetheart via text message, tell him or her never to contact you again and then change your phone number.