Isaiah 40:3 - Meaning and Application

When the time has come for Zion to be shown favor, and the appointed time has arrived, God’s people must be ready for the mercy he means to give them. They need repentance and faith, and this is why we hear the voice of one crying in the wilderness. This can be applied to the prophets who were with the captives in their wilderness-like condition, and who, when they saw deliverance drawing near, urged the people to prepare for it. They also assured them that every difficulty in the way of their return would be removed. It is a good sign that mercy is being prepared for us when we see God’s grace preparing us for it (Psalm 10:17).

But this passage must finally be applied to John the Baptist. Though God was the one speaking, John was the voice crying in the wilderness, and his work was to prepare the way for the Lord, that is, to make people ready to receive Christ’s gospel. The way of the Lord is prepared, first, by repentance for sin. That was what John the Baptist preached to all Judah and Jerusalem (Matthew 3:2, Matthew 3:5), and by doing so he made ready a people prepared for the Lord (Luke 1:17).

The alarm is sounded, and everyone must pay attention at their own risk. God is coming in mercy, and we must prepare for him (Isaiah 40:3-5). If we apply this to the captivity, it means that whatever hard things stand in the way of the return, they will be removed. This voice in the wilderness, with divine power working through it, sends workers ahead to level the road. But it also gives a call to duty, and that same duty is ours as we prepare for Christ to enter our hearts.

We must first get into a heart state that is ready to receive Christ and his gospel: “Prepare the way of the Lord.” We should prepare ourselves for him and remove whatever blocks his entrance. Make room for Christ. Make a straight highway for him. If he prepares the end for us, we should surely prepare the way for him. Prepare for the Savior. Lift up your heads, O gates (Psalm 24:7, Psalm 24:9). Prepare for salvation, the great salvation, and also for smaller acts of rescue. Let us become fit to receive them, and then God will carry them out. We must not get in our own way or block our own door, but make a highway for him, even in ground that seems like a desert. This is what he waits for, so that he may show grace.

We must also let God’s grace level our hearts. Those kept from comfort in Christ because they are crushed and discouraged are the valleys that must be raised up. Those kept from comfort because they are proud of their own merit and worth are the mountains and hills that must be made low. Those who have taken offense at God’s word and ways, who are stubborn and ready to resist what is plain and easy because it does not fit their sinful desires or worldly interests, are the crooked paths that must be made straight and the rough places that must be made smooth. If the gospel of Christ is heard fairly, it cannot fail to be received. This is how the way of the Lord is prepared, and this is how God prepares his own way in all the vessels of mercy, the people whose hearts he opens as he opened Lydia’s.

When this is done, the glory of the Lord will be revealed (Isaiah 40:5). When the captives are prepared for deliverance, Cyrus will proclaim it, and only those whose hearts the Lord has stirred will benefit from it. He will give them courage and resolve to push through the discouragements in their way and treat the hills, valleys, and rough places as nothing. When John the Baptist has preached repentance, self-denial, and reform for a time, and has so made ready a people prepared for the Lord (Luke 1:17), then the Messiah himself will be shown in his glory. He will work miracles, which John did not, and by his grace, which is his glory, he will comfort and heal those whom John had convicted. This showing of divine glory will be a light for the Gentiles too. All flesh will see it together, not just the Jews. They will see it, admire it, and welcome it, just as the return from captivity was noticed by nearby nations (Psalm 126:2). It will also prove that God’s word has been fulfilled, for not one part of it will fail. The mouth of the Lord has spoken it, and therefore the hand of the Lord will bring it about.

Second, we must trust the word of the Lord, not any human strength. Since the mouth of the Lord has spoken, this voice must also cry out, “The word of our God stands forever” (Isaiah 40:8). When God’s promises of salvation are fulfilled fully and on time, it shows that his word is sure and can be trusted. We are prepared for deliverance when we depend wholly on God’s word and build our hope on it, with full assurance that it will not shame us. In that trust, we must come to see that all flesh is grass, weak and fading.

Human power, when it stands against deliverance, does not need to be feared. It will be like grass before the word of the Lord, withering and being trampled down. The proud Babylonians, who think Jerusalem’s ruin will last forever, are only like grass blown on by the Spirit of the Lord. He makes them nothing and dries up all their glory. The word of the Lord, which promises deliverance, will stand forever, and their enemies cannot stop its fulfillment.

Human power, when it seems to be helping deliverance, also must not be trusted. It is only grass when compared with the word of the Lord, which alone is a firm ground for our hope. When God is about to save his people, he will turn them away from trusting in creatures and from looking for help from hills and mountains. Those supports will fail them, and their hopes in them will be disappointed. The Spirit of the Lord will blow on them, because God will not allow any creature to compete with him for his people’s hope and confidence. Since only his word will stand forever, our faith must rest on that word alone. When we are brought to that point, and not before, we are ready for mercy.

The word of our God, that glory of the Lord now being revealed, is the gospel, along with the grace it brings to us and works in us. It will stand forever, and this is the comfort of all believers when they see every creature comfort withering away like grass. The apostle applies this to the word preached through the gospel, which lives and lasts forever, like the imperishable seed by which we are born again (1 Peter 1:23-25).

To prepare the way for the Lord, we must be convinced of the emptiness of all created things. “All flesh is grass” means that every human being is weak and short-lived. We are like that ourselves, so we cannot save ourselves. Our friends are like that too, so they cannot save us either.

All the beauty in created things, the very thing that can make them seem lovely, is like the flower of grass. It fades quickly, so it cannot win God’s favor for us. We are dying creatures, and all our comforts in this world are dying comforts too. For that reason, they cannot be the happiness our immortal souls need. We must look farther for salvation and farther for our true portion.

We also must be convinced of the trustworthiness of God’s promise. The word of the Lord can do for us what all flesh cannot. Since it stands forever, it can give us a happiness that lasts as long as our souls, which must live forever. The things we do not see, but must believe, are eternal.