Irenaeus (c. 125–c. 202)
When in the end the Church shall be suddenly caught up from this, it is said, “There shall be tribulation such as has not been since the beginning, neither shall be.” For this is the last contest of the righteous, in which, when they overcome they are crowned with incorruption.
Tertullian (c. 155–c. 225)
“As yet those whom the coming of the Lord is to find on the earth, have not been caught up into the air to meet Him at His coming” (TS, 55).
Caught up=Grk 'harpazo'=Latin/English transliteration 'rapture'
This is from a period which was quite a bit earlier than Darby, and Irenaeus is in direct discipleship lineage from the Apostle John.
And before that, the Lord Jesus Christ revealed it to Paul, who put it on paper. He said the departure of the church is before Jacob's trouble and the man of perdition is revealed. We are more than 10007 years from that point, yet there is still death, pain and tears.
Tet is a huge fraud, and I don't think he was ever a believer.