John 14:1

Let not your heart be troubled

(μη ταρασσεσθω υμων η καρδια). Not here the physical organ of life (Luke 21:34), but the seat of spiritual life (πνευμα, ψυχη), the centre of feeling and faith (Romans 10:10), "the focus of the religious life" (Vincent) as in Matthew 22:37. See these words repeated in John 14:27. Jesus knew what it was to have a "troubled" heart (John 11:33; John 13:31) where ταρασσω is used of him. Plainly the hearts of the disciples were tossed like waves in the wind by the words of Jesus in John 13:38.Ye believe... believe also

(πιστευετε... κα πιστευετε). So translated as present active indicative plural second person and present active imperative of πιστευω. The form is the same. Both may be indicative (ye believe... and ye believe), both may be imperative (believe... and believe or believe also), the first may be indicative (ye believe) and the second imperative (believe also), the first may be imperative (keep on believing) and the second indicative (and ye do believe, this less likely). Probably both are imperatives (Mark 11:22), "keep on believing in God and in me."