KJV: For when they shall say, Peace and safety; then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape.
NASB: While they are saying, "Peace and safety!" then destruction will come upon them suddenly like labor pains upon a woman with child, and they will not escape.
KJV: And we beseech you, brethren, to know them which labour among you, and are over you in the Lord, and admonish you;
NASB: But we request of you, brethren, that you appreciate those who diligently labor among you, and have charge over you in the Lord and give you instruction,
KJV: So that we ourselves glory in you in the churches of God for your patience and faith in all your persecutions and tribulations that ye endure:
NASB: therefore, we ourselves speak proudly of you among the churches of God for your perseverance and faith in the midst of all your persecutions and afflictions which you endure.
KJV: And to you who are troubled rest with us, when the Lord Jesus shall be revealed from heaven with his mighty angels,
NASB: and to give relief to you who are afflicted and to us as well when the Lord Jesus will be revealed from heaven with His mighty angels in flaming fire,
KJV: When he shall come to be glorified in his saints, and to be admired in all them that believe (because our testimony among you was believed) in that day.
NASB: when He comes to be glorified in His saints on that day, and to be marveled at among all who have believed-- for our testimony to you was believed.
KJV: But we are bound to give thanks alway to God for you, brethren beloved of the Lord, because God hath from the beginning chosen you to salvation through sanctification of the Spirit and belief of the truth:
NASB: But we should always give thanks to God for you, brethren beloved by the Lord, because God has chosen you from the beginning for salvation through sanctification by the Spirit and faith in the truth.