Firstly the shot is used to start [Ozymandias] in the flashback when Skyler is packing away the clown she sold.
The shot itself holds so much meaning because of the phone placed right next to the knives. It shows how much different Skyler is and how strong she’s become. Instead of calling for help (reaching for the phone) she reaches for a knife to defend herself and her family from the monster Walt has become.
Interestingly enough, the knife she grabs is the same knife Walt puts away in Season 2, Episode 1 “Seven Thirty-Seven”. [x]
(Source: jessepinkmanist, via slapmymind)