a rope of sand

rope of sand

Something that is not as strong or stable as it seems. Yes, you're a fool to trust him, and this allegiance will soon prove to be a rope of sand. I thought I finally had a strong bond with my mother, but it was just a rope of sand—she's left us once again.
See also: of, rope, sand

a rope of sand

used in allusion to something that provides only illusory security or coherence. literary
See also: of, rope, sand