Psalm 1:1 Blessed is the man that walketh not in the counsel of the ungodly, nor standeth in the way of sinners, nor sitteth in the seat of the scornful.
Psa 1:2 But his delight is in the law of the LORD; and in his law doth he meditate day and night.
Psa 1:3 And he shall be like a tree planted by the rivers of water, that bringeth forth his fruit in his season; his leaf also shall not wither; and whatsoever he doeth shall prosper.
V1 shows us what the blessed man doesn't do
~ The blessed man doesn't enter into the downward spiral into the sinfulness of the ungodly.
V2 shows us what the blessed man does do
~ The blessed man delights and meditates day and night on the word of God.
V3 shows us the result of the blessed man's meditations
(Whereas the ungodly man is in a downward spiral toward being a scoffer at the godly, the blessed man enters into a spiritual upward spiral towards godliness)
1 He's like a tree planted by the rivers of water - This pictures the tree whose roots feed off the underground streams from the river.
2 H's fruitful in his season - This man will be fruitful no doubt. This reminds of the fruit of the Holy Spirit (Galatians 5:22,23).
3 His leaf doesn't whither - Whether there is drought around us or the seasons of life change our leaf won't whither but be full of life.
4 All he does prospers - We are prosperous in doing God's will for our life. The prospering doesn't mean we won't have trouble but we are still prosperous spiritually in our relationship with God. We prospers because the word of God provides the strength, wisdom and guidance to prosper.
Summary: The blessed man delights and meditates on God's word all the time. The result of his delight and meditation is that his roots do deep into the bible and those deep roots in the bible feed and nourish him so that he's fruitful in all seasons of life. He doesn't have to try and grow and be fruitful, it will happen as a result of delighting and meditating on God's word.