海誓山盟

exchange solemn vows and pledges; lovers pledge of eternal loyalty until the seas dry up and rocks decay; make a solemn pledge (oath) of (eternal) love; Oaths high as the mountains and vows deep as the ocean were exchanged.; plight one's troth; swear by the sea and by the hills; swear inviolable oaths of mutual love and fidelity; swear unchanging fidelity in oaths high as the mountains and deep as the ocean; They swore a great oath that neither would love anyone else.; They swore together an oath of fidelity, vowing never to change until their lives' end.; (make) a solemn pledge of love; engagement irrévocable (de deux amants)