40  The prophet having now foretold the Babylonish captivity, chap.Isa 39:6-7,
does here arm his people against it by the consideration of their certain deliverance out of it, and their blessed condition after it, as in other things so especially in the coming of the Messiah, and the great and glorious privileges conferred upon God's church and people in his days. The preaching of the gospel by John the baptist and the apostles, Isa 40:1-11.
The power and wisdom of God in governing the world, Isa 40:12-17.
The folly of idolatry, Isa 40:18-26.
God knows the state of his people, and both can and will protect them, Isa 40:27-31.

40:1 Ye - Ye prophets and ministers.

40:2 Warfare - The time of her captivity, and misery. Double - Not twice as much as her sins deserved, but abundantly enough to answer God's design in this chastisement, which was to humble and reform them, and to warn others by their example.

40:3 The voice - An abrupt speech. Methinks I hear a voice.Wilderness - This immediately relates to the deliverance of the Jews out of Babylon, and smoothing their passage from thence to Judea, which lay through a great wilderness; but principally to their redemption by the Messiah, whose coming was ushered in by the cry of John the baptist, in the wilderness. Prepare ye the way - You to whom this work belongs. He alludes to the custom of princes who send pioneers before them to prepare the way through which they are to pass. The meaning is, God shall by his spirit so dispose mens hearts, and by his providence so order the affairs of the world, as to make way for the accomplishment of his promise. This was eminently fulfilled, when Christ, who was, and is God, blessed for ever, came into the world in a visible manner.

3 

3:8 But be not ye ignorant - Whatever they are. Of this one thing - Which casts much light on the point in hand. That one day is with the Lord as a thousand years, and a thousand years as one day - Moses had said, Psa 90:4, "A thousand years in thy sight are as one day;"which St. Peter applies with regard to the last day, so as to denote both his eternity, whereby he exceeds all measure of time in his essence and in his operation; his knowledge, to which all things past or to come are present every moment; his power, which needs no long delay, in order to bring its work to perfection; and his longsuffering, which excludes all impatience of expectation, and desire of making haste. One day is with the Lord as a thousand years - That is, in one day, in one moment he can do the work of a thousand years. Therefore he "is not slow:" he is always equally ready to fulfil his promise. And a thousand years are as one day - That is, no delay is long to God. A thousand years are as one day to the eternal God.Therefore "he is longsuffering:" he gives us space for repentance, without any inconvenience to himself. In a word, with God time passes neither slower nor swifter than is suitable to him and his economy; nor can there be any reason why it should be necessary for him either to delay or hasten the end of all things. How can we comprehend this? If we could comprehend it, St. Peter needed not to have added, with the Lord.

3:9 The Lord is not slow - As if the time fixed for it were past. Concerning his promise - Which shall surely be fulfilled in its season. But is longsuffering towards us - Children of men.Not willing that any soul, which he hath made should perish.

3:10 But the day of the Lord will come as a thief - Suddenly, unexpectedly. In which the heavens shall pass away with a great noise - Surprisingly expressed by the very sound of the original word. The elements shall melt with fervent heat - The elements seem to mean, the sun, moon, and stars; not the four, commonly so called; for air and water cannot melt, and the earth is mentioned immediately after. The earth and all the works - Whether of nature or art. That are therein shall be burned up - And has not God already abundantly provided for this?

1. Bythe stores of subterranean fire which are so frequently bursting out at Aetna, Vesuvius, Hecla, and many other burning mountains.
2. By the ethereal (vulgarly called electrical) fire, diffusedthrough the whole globe; which, if the secret chain that now binds it up were loosed, would immediately dissolve the whole frame of nature.
3. By comets, one of which, if it touch the earth in its course toward the sun, must needs strike it into that abyss of fire; if in its return from the sun, when it is heated, as a great man computes, two thousand times hotter than a red - hot cannonball, it must destroy all vegetables and animals long before their contact, and soon after burn it up.

3:11 Seeing then that all these things are dissolved - To the eye of faith it appears as done already. All these things - Mentioned before; all that are included in that scripturalexpression, "the heavens and the earth;" that is, the universe.On the fourth day God made the stars, Gen 1:16, which will be dissolved together with the earth. They are deceived, therefore, who restrain either the history of the creation, or this description of the destruction, of the world to the earth and lower heavens; imagining the stars to be more ancient than the earth, and to survive it. Both the dissolution and renovation are ascribed, not to the one heaven which surrounds the earth, but to the heavens in general, Pe2 3:10, Pe2 3:13, without any restriction or limitation. What persons ought ye to be in all holy conversation - With men. And godliness - Toward your Creator.

3:12 Hastening on - As it were by your earnest desires and fervent prayers. The coming of the day of God - Many myriads of days he grants to men: one, the last, is the day of God himself.

3:13 We look for new heavens and a new earth - Raised as it were out of the ashes of the old; we look for an entire new state of things. Wherein dwelleth righteousness - Only righteous spirits. How great a mystery!

3:14 Labour that whenever he cometh ye may be found in peace - May meet him without terror, being sprinkled with his blood, and sanctified by his Spirit, so as to be without spot and blameless. Isa 65:17; Isa 66:22.

1 

1:1 The beginning of the Gospel of Jesus Christ - The evangelist speaks with strict propriety: for the beginning of the Gospel is in the account of John the Baptist, contained in the first paragraph; the Gospel itself in the rest of the book. Mat 3:1; Luk 3:1

1:2  Mal 3:1

1:3  Isa 40:3.

1:4 Preaching the baptism of repentance - That is, preaching repentance, and baptizing as a sign and means of it.

1:7 The latchet of whose shoes I am not worthy to unloose - That is, to do him the very meanest service.