Passage
I have no greater joy than this, to hear that my children are walking in the truth.
3 John 1:4 (LSB)
Nearby Context
3 John 1:2 Beloved, I pray that in all respects you may prosper and be in good health, just as your soul prospers.
3 John 1:3 For I rejoiced greatly when brothers came and bore witness to your truth, that is, how you are walking in truth.
3 John 1:4 I have no greater joy than this, to hear that my children are walking in the truth.
3 John 1:5 Beloved, you are acting faithfully in whatever work you do for the brothers, and are doing this though they are strangers;
3 John 1:6 and they bore witness to your love before the church. You will do well to send them on their way in a manner worthy of God.
Study Lenses
The verse centers on "greater", "than", "hear", "children", "walking", and "truth". It is saying that the verse draws attention to "greater" and "than", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 3's "For I rejoiced greatly when brothers came..." into verse 5's "Beloved you are acting faithfully in whatever...", so "greater" and "than" belong inside that flow. In 3 John context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "greater" and "than" with trust shaped by these words, not by a vague optimism outside the passage.