What is the scriptural basis for the teaching that the 7th Trumpet introduces and contains the 7 bowls of wrath? The Bible doesn't specifically say so. Revelation 10:7 says, "In the days of the voice of the seventh angel, when he shall begin to sound, the mystery of God should be finished. . .". Because of the phrase "in the days of", some people understand this verse to mean that the 7th Trumpet will sound over a prolonged period of time during which all 7 bowl judgments will play out. But we often ignore the next phrase that says "when he shall begin to sound" which actually qualifies the first phrase. Doesn't this second phrase indicate that the mystery of God will be finished the moment the 7th Trumpet begins to sound rather than the mystery being completed over a prolonged period of time? It seems to me that "in the days of" does not necessarily imply a prolonged period of time; it may mean that the 7th Trumpet was not going to immediately the statement was made in chapter 10 but at a later time.
Secondly, what constitutes the third woe judgment?
It appears the position one takes on the above questions depends on where one places the ministry of the Two Witnesses. The 7th Trumpet sounds in Revelation 11:15 shortly after the resurrection and ascension of the Two Witnesses. So, if you believe the ministry of the Two Witnesses occurs in the first half of the Tribulation, then you're likely to place the sounding of the 7th Trumpet at mid-Tribulation whereas if you think the Two Witnesses minister in the second half of the Tribulation, you will place the sounding of the 7th Trumpet on the very last day of the Tribulation. Now, if you believe the Two Witnesses minister in the second half of the Tribulation and that the 7th Trumpet sounds on the final day of the Tribulation as I do, it becomes difficult to sustain the view that the 7th Trumpet contains the 7 bowls of wrath for the obvious reason that there will be no time for all 7 bowl judgments to play out if the 7th Trumpet sounds on the final day of the Tribulation, the same day that Jesus returns to earth in glory. This is because all 7 bowl judgments will likely require at least a couple of weeks to be accomplished, rather than a single day.
I look forward to further insights on these issues.