Some of these headers are taken directly from Ludlow's book.
Living, Loving God
In the first two verses, God gives comfort and forgives his people. In Isaiah 40:2 the message to his people is, "that her warfare is accomplished, that her iniquity is pardoned."
To me, this means that if we keep the commandments (warfare … read 2 Tim 4:7) then we will be forgiven of our sins and comforted by God.
The other example of this attribute is comparing idols to God (Isaiah 40:18-20).
If we compare our worship of God to those who make graven images, by far God outshines and outperforms any of the dumb idols man makes with his hands and then worships. Idols cannot forgive or live or love. Only God can do this.
"The voice of him that crieth in the wilderness, Prepare ye the way of the Lord, make straight in the desert a highway for our God." (Isaiah 40:3)
John the Baptist was an "Elias" or forerunner to Jesus Christ.
Creative, Powerful God
With his power, "every valley shall be exalted, and every mountain and hill shall be made low (Isaiah 40:4). The nations are a drop in a bucket and small dust compared to God (Isaiah 40:15).
Supreme, Eternal God
Man's nature is transitory and unsteady. Our flesh is like grass that withers and our good actions are like flowers that fade with time (Isaiah 40:6-7). We are even likened to grasshoppers (Isaiah 40:22). But our God is supreme and eternal. His word will stand forever (Isaiah 40:8) and he makes the princes of the earth nothing and the judges vain (Isaiah 40:23).
Active, Caring God
God feeds his flock, gathers his lambs, carries them in his bosom and gently leads (Isaiah 40:11). He calls his children by their names (Isaiah 40:26).
Consistent, All-knowing God
God has all power and knowledge. He never tires or wearies. No one can fathom his knowledge and wisdom (Isaiah 40:28).
Trust in God
To those that trust in the Lord and "wait upon" him, their strength shall be renewed and "that shall mount up with wings as eagles; they shall run, and not be weary; and they shall walk, and not faint." (Isaiah 40:31)
A similar promise is given in the Doctrine and Covenants to those who obey the Word of Wisdom (see D&C 89).
The overall message I get from Isaiah 40 is that the personage we worship is truly awesome and supreme. I feel a sense of nothingness and am humbled. I feel similar to how Moses must have felt after he visited with God and saw the endless creations of God. Moses was left to himself for many hours, unable to move for lack of strength. When he regained his strength, he said to himself, "Now, for this cause I know that man is nothing, which thing I never had supposed." (Moses 1:10)
It is easy for us to lose perspective when we see all the things our hands have made … the cities, the cars, the towers, the military machines, the boats, the bridges, the rockets, space shuttles, satellites, and everything imaginable man has created. But all these things are nothing compared to the grandeur and ultimate power of God.
We worship the ultimate source of power and knowledge and wisdom in the universe. This is the lesson I learned while reading Isaiah 40.