There’s no such thing as a free lunch – so the saying goes. The LORD begs to differ:
Isaiah 55:1-3 "Come, all you who are thirsty, come to the waters; and you who have no money, come, buy and eat! Come, buy wine and milk without money and without cost. 2 Why spend money on what is not bread, and your labour on what does not satisfy? Listen, listen to me, and eat what is good, and your soul will delight in the richest of fare. 3 Give ear and come to me; hear me, that your soul may live. I will make an everlasting covenant with you, my faithful love promised to David.
A free lunch is exactly the kind of thing our heavenly Father provides. After all, if we ask for bread, will He give us a stone? If we ask for an egg, will He give us a snake? (Matthew 7:9-10) No, He gives us free sunshine, free air, free water, free life. His very nature is to offer us free sustenance.
How does this sustenance come? Through His word. Notice how the LORD says “Listen, Give ear, Hear me.” Whatever God has for us, it’s dished up in the word. See verses 10-11:
10 As the rain and the snow come down from heaven, and do not return to it without watering the earth and making it bud and flourish, so that it yields seed for the sower and bread for the eater, 11 so is my word that goes out from my mouth: It will not return to me empty, but will accomplish what I desire and achieve the purpose for which I sent it.
Just as rain brings grain, so the word brings food to us. The purpose for which God sends his word is to bring life. It’s like rain on a parched land. It makes people dying with thirst to bud and flourish.
Back in verse 3, simply to hear this word brings life to our souls. Why? Because through God's word we receive His “faithful love promised to David.”
Now think about that!
In the words of the King James version, He offers "the sure mercies of David" to peoples and nations. He invites the world into His covenant with David.
When Isaiah wrote this, King David was long dead. Yet all Israel knew that David foreshadowed the true King of the Jews.
In Isaiah 9, we read about the Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace who reigns on David's throne. Christ is the true David and Isaiah knew it.
In Isaiah 11 he prophesies about Christ as the shoot of Jesse. The Messiah is the Ideal David, filled with the Spirit of wisdom and understanding. He is a Cosmic King to bring justice and righteousness to the world.
Thus "the sure mercies of David" refers to the Father’s covenant love for His Son. This is what God wants to give us: He wants the world to enjoy His love for Christ.
In Isaiah 42, we read about how the Father feels towards Christ:
"Here is my servant, whom I uphold, my chosen one in whom I delight; I will put my Spirit on him and he will bring justice to the nations.
Those are the sure mercies of David. That’s the Father’s everlasting love for His Son.
From all eternity the Son has been the true David – the Anointed King. He is the Father’s everlasting delight and He pours His Spirit without measure onto Christ.
This is the everlasting covenant. These are the sure mercies of David. They’re all found in Jesus. And in God’s word we are given Christ for free.
That’s why we read our Bibles. That’s why we have preaching. That’s why we encourage each other with the word. Because in God’s word, God’s Son is offered. And He is Bread for the hungry. He offers Living Waters for the thirsty. All without money and without cost. We simply “listen” / “give ear” / “hear” our Father and through the gift of Christ our souls will live.
Why listen to God's word? To feast on Christ.
This is taken from the introduction to my Isaiah talks
It's also the theme of my latest devotional's preface