Jeremiah 17:5-8 paints a picture of two different types of people, those who trust in man and those who trust in the Lord. The picture that it paints reveals the stark contrast between the two.
Verses 5 and 6 tell us that the person who trusts in man is cursed. That person is compared to a bush in the wastelands. A wasteland is barren. It cannot sustain life. So, a bush in a wasteland cannot survive. It cannot prosper. A person who trusts in man will not see prosperity. These verses also say that the person who trusts in mere flesh will dwell in the parched places of the desert. The desert is dry. There is no water to sustain life. A person who trusts in man will not find what is needed to sustain the inner life of the soul: living water. As a result, the heat of life's struggles and life's troubles will leave him parched and dry. His thirst will never be quenched.
Verses 7 and 8 tell us that the person who trusts in the Lord, who makes the Lord his hope and his confidence, is blessed. This person is compared to a tree planted along the banks of a river. A tree planted on the banks of a river has roots that reach down into the water. Because it has the river's never-ending supply of water to nourish it, the tree can withstand heat and drought. The person who trusts in the Lord is rooted in Christ, the living water. Because he is rooted in Christ, he has a never-ending supply of the living water needed to sustain the inner life of his soul. He is able to withstand the heat and drought of life's struggles and troubles. This person will never be thirsty.
In this life, we have a choice. We can be the person who trusts in man or we can be the person who trusts in the Lord. It is a choice between life and death (Deuteronomy 30:19). When you look at the picture painted in Jeremiah 17:5-8, the choice should be easy.