Have you ever gotten one of those emails that read, "Help I'm in a foreign country and I've been robbed"? I confess that the first time I received one of those emails my initial response was to be concerned since the person I received the email from was just an acquaintance. But as I read further, I suspected it was a hoax. And it was. In today's passage, the Thessalonians have heard some false reports (kind of like getting those spam emails) and they are very concerned. So Paul writes to remind them of the truth. The best safeguard against deception is the truth.
In the second chapter of 2 Thessalonians, Paul tells them how to not be deceived. They must: 1) know the truth; 2) be thankful for the truth; 3) stand firm and hold fast to the truth.
The Thessalonians were feeling unsettled and alarmed because they had heard that the day of the Lord had already come! Paul told them previously of the hope that they have in Christ's second coming and about the day of the Lord in 1 Thessalonians. And now they think they've missed it!
Paul eases their mind by telling them that the day of the Lord has not yet arrived. The "man of lawlessness" must be revealed first, before the day of the Lord arrives. (2 Thessalonians 2:3). They will not be deceived if they know the truth of the day of the Lord and the "man of lawlessness."
Secondly, the Thessalonians won't be deceived if they are thankful for the truth who of they are in Christ. 2 Thessalonians 2:13 is a beautiful picture of the trinity. The are loved by Christ, chosen by God and sanctified by the Spirit. If they remember who they are, then they won't be deceived.
Lastly, the Thessalonians won't be deceived if they stand firm and hold fast to the truth (2 Thessalonians 2:15-17) They are not to hold God's truth in a careless way, but grasp it firmly with power and never let it slip from them. If they do that, they will have eternal encouragement and good hope that empowers them to do good deeds.
For us, we won't be deceived if we 1) know the truth - we must be in the Word and the Word must be in us; 2) are thankful for the truth in Christ that we are loved, chosen and saved; 3) if we stand firm and hold fast to the truth of Christ against the lies of the world and the enemy.
May the truth of Christ set us free and keep us from being deceived!