The trees of the LORD are full of sap ; the cedars of Lebanon, which he hath planted;
KJV Psalm 104:16
The cedars of Lebanon i.e. the trees of the LORD, is a symbolic reference to God’s people. His trees are “full” because of where he planted them:
The righteous shall flourish like the palm tree: he shall grow like a cedar in Lebanon. [13] Those that be planted in the house of the LORD shall flourish in the courts of our God.
KJV Psalm 92:12-13
To be planted in the LORD’s house i.e. to join his family, is to be planted in Christ:
For if we have been planted together in the likeness of his death, we shall be also in the likeness of his resurrection:
KJV Romans 6:5
When we are planted ✝️ in/with him, that’s when we are full as the psalmist said and to be full in Christ is to never hunger or thirst again.
How does one be planted to be full in Christ you ask?
Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life.
KJV Romans 6:4