What does Psalm 52:8 mean?

In this psalm, David condemns a man who used evil speech to murder many innocent people (Psalm 52:1–4; 1 Samuel 22:9–10, 17–19). David fully expects God to repay the wicked person as an example to others (Psalm 52:5–7). In contrast, David expects to be blessed by God on account of submissive faith.

David compares himself to a green olive tree. This picture is meant to imply prosperity and longevity (Psalm 1:3). Olive trees are renowned for their long lives and continual productivity. Jeremiah 17:7–8 states: "Blessed is the man who trusts in the Lᴏʀᴅ, whose trust is in the Lᴏʀᴅ. He is like a tree planted by water, that sends out it roots by the stream, and does not fear when heat comes, for its leaves remain green, and is not anxious in the year of drought, for it does not cease to bear fruit." This is a direct contrast to the wicked who will be "uprooted" (Psalm 52:5).

Like David, who was a blessing to Israel, believers who live in a close relationship with the Lord are a blessing to others and bear the fruit of the Spirit (Galatians 5:22–23).