"Nevertheless we, according to his promise, look for new heavens and a new earth, wherein dwelleth righteousness. Wherefore, beloved, seeing that ye look for such things, be diligent that ye may be found of him in peace, without spot, and blameless."
2 Peter 3:13-14
“Nevertheless we, according to his promise,”
According to Jesus’ Word, He will return to earth for His children!
“Look for new heavens and a new earth,”
He will replace this old sin-cursed earth with His new creation.
“Wherein dwelleth righteousness.”
Note this beautiful feature in the new earth, there will be no sin! The Word says, “wherein dwelleth righteousness.” As finite sinners, even though we are saved, we cannot fully comprehend how beautiful a world without sin will be.
“The new heavens and earth will be “holy.” They will be the home of righteousness forever”  (Barnes).
“Wherefore, beloved, seeing that ye look for such things,”
Because we believers are looking for such a world to come, it should make a difference in how we live in this world.
“Be diligent that ye may be found of him in peace,”
When our dear Savior returns, how will He find you? Watching, ready? Sleeping and not caring?
“And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith” (Philippians 3:9).
Believers, we have peace with God as a result of our salvation, but unfortunately, we do not always encourage peace within the ranks of our brothers and sisters in Christ. Peter understands that if we are going to spend eternity with these believers, we ought to be doing our best to live at peace with them while we are waiting for the Lord’s return.
We Christians are expected to be living “without spot.”
“…at the coming marriage feast of the Lamb, in contrast to 2 Peter 2:13, ‘Spots they are and blemishes while they feast,’ not having on the King’s pure wedding garment.” 
We are striving to live above reproach and avoiding unnecessary offenses.
“And the very God of peace sanctify you wholly, and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ” (1 Thessalonians 5:23).
Our belief in His soon second coming should be shaping our behavior as we look for His return.
 Albert Barnes, Albert Barnes’ Notes on the Bible, the electronic version in eSword.
 Jamison, Fausset, and Brown. Jamison-Fausset-Brown’s Commentary, the electronic version in eSword.