New Revised Standard Version
not to be quickly shaken in mind or alarmed, either by spirit or by word or by letter, as though from us, to the effect that the day of the Lord is already here.

Contemporary English Version
not to be easily upset or disturbed by people who claim the Lord has already come. They may say they heard this directly from the Holy Spirit, or from someone else, or even that they read it in one of our letters.

New American Bible
not to be shaken out of your minds suddenly, or to be alarmed either by a “spirit,” or by an oral statement, or by a letter allegedly from us to the effect that the day of the Lord is at hand.

Douay-Rheims Bible
That you be not easily moved from your sense nor be terrified, neither by spirit nor by word nor by epistle. as sent from us, as if the day of the Lord were at hand.

That you be not easily moved from your sense nor be terrified, neither by spirit nor by word nor by epistle. as sent from us, as if the day of the Lord were at hand.

shaken.

Isaiah 7:2 And they told the house of David, saying: Syria hath rested upon Ephraim, and his heart was moved, and the heart of his people, as the trees of the woods are moved with the wind.

Isaiah 8:12,13 Say ye not: A conspiracy: for all that this people speaketh, is a conspiracy: neither fear ye their fear, nor be afraid. . . .

Isaiah 26:3 The old error is passed away: thou wilt keep peace: peace, because we have hoped in thee.

Matthew 24:6 And you shall hear of wars and rumours of wars. See that ye be not troubled. For these things must come to pass: but the end is not yet.

Mark 13:7 And when you shall hear of wars and rumours of wars, fear ye not. For such things must needs be: but the end is not yet.

Luke 21:9,19 And when you shall hear of wars and seditions, be not terrified. These things must first come to pass: but the end is not yet presently. . . .

John 14:1,27 Let not your heart be troubled. You believe in God: believe also in me. . . .

Acts 20:23,24 Save that the Holy Ghost in every city witnesseth to me, saying: That bands and afflictions wait for me at Jerusalem. . . .

Ephesians 5:6 Let no man deceive you with vain words. For because of these things cometh the anger of God upon the children of unbelief.

1 Thessalonians 3:3 That no man should be moved in these tribulations: for yourselves know that we are appointed thereunto.

by spirit.

Deuteronomy 13:1-5 If there rise in the midst of thee a prophet or one that saith he hath dreamed a dream, and he foretell a sign and a wonder, . . .

Jeremiah 23:25-27 I have heard what the prophets said, that prophesy lies in my name, and say: I have dreamed, I have dreamed. . . .

Micah 2:11 Arise ye, and depart, for there is no rest here for you. For that uncleanness of the land, it shall be corrupted with a grievous corruption.

Matthew 24:4,5,24 And Jesus answering, said to them: Take heed that no man seduce you. . . .

2 Peter 2:1-3 But there were also false prophets among the people, even as there shall be among you lying teachers who shall bring in sects of perdition and deny the Lord who bought them: bringing upon themselves swift destruction. . . .

1 John 4:1,2 Dearly beloved, believe not every spirit, but try the spirits if they be of God: because many false prophets are gone out into the world. . . .

Revelation 19:20 And the beast was taken, and with him the false prophet who wrought signs before him, wherewith he seduced them who received the character of the beast and who adored his image. These two were cast alive into the pool of fire burning with brimstone.

nor by letter.

1 Thessalonians 4:15 For this we say unto you in the word of the Lord, that we who are alive, who remain unto the coming of the Lord, shall not prevent them who have slept.

2 Peter 3:4-8 Saying: Where is his promise or his coming? For since the time that the fathers slept, all things continue as they were from the beginning of the creation. . . .