In John 15:1-7 we find Jesus delivering a monologue in which he describes a scene common to first-century Palestinians: a vineyard in which a vine is cultivated to produce fruit. Drawing out the analogy, the disciples are branches who draw their life sustenance from their connection to the vine. This image aligns well with the metaphor of Jesus the Life-Giver.  As he continues to explain, those who remain in him will bear much fruit. Inversely, those who are separated from him can do nothing without the life that he provides.