Paul was quite concerned that there were those who were teaching that the Day of the Lord had already come. While it is from Paul that we learn much about the Life and authority of Christ that is ours by right to know now, he revealed that there is much more to come before we can know the Day of the Lord in its fullness.

II Thessalonians 2:1-3—Now we beseech you, brethren, by the coming (with regard to the parousía) of our Lord Jesus Christ, and by (concerning) our gathering together unto Him, 2that ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the Day of Christ is at hand (has already come). Let no man deceive you by any means: for that Day shall not come, except there come a falling away (the apostasy, from the Greek he apostasía,) first, and that man of (the) sin be revealed, the son of perdition (the mature son of the destruction, the one who carries with him the eternal ruin).

(MSG) 1-3—Now, friends, read these next words carefully. Slow down and don't go jumping to conclusions regarding the day when our Master, Jesus Christ, will come back and we assemble to welcome him. Don't let anyone shake you up or get you excited over some breathless report or rumored letter from me that the day of the Master's arrival has come and gone. Don't fall for any line like that.
3-5 Before that day comes, a couple of things have to happen. First, the Apostasy. Second, the debut of the Anarchist, a real dog of Satan. He'll defy and then take over every so-called god or altar. Having cleared away the opposition, he'll then set himself up in God's Temple as "God Almighty." Don't you remember me going over all this in detail when I was with you? Are your memories that short?

Paul here begins telling of the turmoil that shall precede the prophetic Day of Christ. How necessary it is that much prayer and preparation precede that Day!

FATHER, my heart yearns for that Day in which Your only begotten Son will receive His full inheritance. I know there is much preparation needed in Christ’s Body before that Day arrives. Please send Your Spirit upon the ministries Your Son at Your right hand has appointed to bring us who are believers to our perfection. Prepare us for the time of trouble. Prepare us for the tribulation Jesus said would come before the Day of His Parousía.

After the tribulation of those days the Son of Man shall appear.—Matthew 24:21-31