slip through one's fingers, to let

slip through someone's fingers

 
1. Lit. to slide through and out of one's grasp. The glass slipped through his fingers and crashed to the ground. The rope slipped through his fingers and followed the anchor to the bottom of the lake.
2. Fig. to escape from someone; to elude someone's capture or control. The prisoner slipped through the sheriff's fingers. Don't let Max slip through your fingers again this time!
See also: finger, slip, through

slip through one's fingers, to let

To fail to seize an opportunity. This metaphor has been around since the seventeenth century. Beaumont and Fletcher used it in The Prophetess (1622, 3.2): “Hold her fast, She’ll slip thorow your fingers like an Eel else.”
See also: let, slip, through