Hang by a thread/hair phrase
Literally, to be connected simply by a single thread, strand, or other similar means.
You're so careless to have your documents hung by a thread like that.
Figuratively, to be at risk of failing, dying, or having a negative consequence.
Our environmental project is hanging by a hair due to the shortage of finance.
She knows that if she fails the exam, her whole future will hang by a thread.
The verb "hang" should be conjugated according to its tense.
This expression, already proverbial in the early 1500s, alludes to Damocles, who vexed King Dionysius with constant flattery. The king invited him to a banquet where Damocles found himself seated under a naked sword suspended by a single hair, symbolizing his insecure position at the court.
The inexplicable or concealed place or state indicates the afterlife.
I'm very sorry for your dad. He's beyond the veil.