“18 The grace of our Lord Jesus Christ be with you all.”
The word “grace” in Greek means favor, joy, and God’s influence in one’s heart. Strong’s# 5485
Without God’s favor, His strength, no Christian can survive any satanic attack. God’s favor is seen in the Holy Spirit living inside the believer. Jesus said in the Book of Luke…
[Luke 10:19] 19 “Look, I have given you the authority to trample on snakes and scorpions and over all the power of the enemy; nothing at all will harm you.
“authority” Refers to the power of God in the name of Jesus. Only Christians have it.
“trample on snakes and scorpions” The Lord has given the believers the power, by His Spirit, to defeat the demonic spirits who are described as snakes, and scorpions. Snakes and scorpions are dangerous venomous animals that with one bite can cause pain and death.
“17 I, Paul, am writing this greeting with my own hand, which is an authenticating mark in every letter; this is how I write.”
Paul was revealing to the church, who he was writing to, how they can recognize his letters. The reason why is because there were many false apostles in the time of Paul. See below.
[2 Corinthians 11:13-15] 13 For such people are false apostles, deceitful workers, disguising themselves as apostles of Christ. 14 And no wonder! For Satan disguises himself as an angel of light. 15 So it is no great surprise if his servants also disguise themselves as servants of righteousness. Their end will be according to their works.
Also, they (the false apostles) were writing letters to the church in Paul’s name, deceiving the church. See below.
[2 Thessalonians 2:1-2] 1 Now concerning the coming of our Lord Jesus Christ and our being gathered to him: We ask you, brothers and sisters, 2 not to be easily upset or troubled, either by a prophecy or by a message or by a letter supposedly from us, alleging that the day of the Lord has come.
Paul wanted to make sure that the Thessalonians would not be deceived by believing a false gospel.
“16 May the Lord of peace himself give you peace always in every way. The Lord be with all of you.”
The Lord alone can give you peace, a peace that no one can comprehend. This peace can only come through prayer. Asking God, to “…guard your hearts and minds in Christ Jesus” –Philippians 4:7.
“in every way” It doesn’t matter the situation you’re in, the Lord’s peace will fill your heart to endure any suffering.