A.T. Robertson Commentary John 15:5

"I am the vine, ye are the branches: He that abideth in me, and I in him, the same beareth much fruit: for apart from me ye can do nothing." — John 15:5 (ASV)

Ye the branches (υμεις τα κληματα). Jesus repeats and applies the metaphor of verse 1.

Apart from me (χωρις εμου). See Eph 2:12 for χωρις Χριστου. There is nothing for a broken off branch to do but wither and die. For the cosmic relation of Christ see Joh 1:3 (χωρις αυτου).