Passage
No one has greater love than this, that one should lay down his life for his friends.
John 15:13 (DBY)
Nearby Context
John 15:11 I have spoken these things to you that my joy may be in you, and your joy be full.
John 15:12 This is my commandment, that ye love one another, as I have loved you.
John 15:13 No one has greater love than this, that one should lay down his life for his friends.
John 15:14 Ye are my friends if ye practise whatever I command you.
John 15:15 I call you no longer bondmen, for the bondman does not know what his master is doing; but I have called you friends, for all things which I have heard of my Father I have made known to you.
Study Lenses
The verse centers on "greater", "love", "than", "should", "down", "life", and "friends". It is saying that the verse draws attention to "greater" and "love", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 12's "This is my commandment that ye love..." into verse 14's "Ye are my friends if ye practise...", so "greater" and "love" belong inside that flow. In John context, the local focus is the identity of Jesus, new birth, eternal life, and belief and unbelief.
A plain takeaway is to answer the verse's own emphasis on "greater" and "love" with trust shaped by these words, not by a vague optimism outside the passage.