Paul spoke of knowing that he had run his course successfully and had received witness that he was acceptable, or sealed. First sealed as belonging to Christ via HS bearing witness to his anointing. Then second as witness he had run his race faithfully and was ready to die with a clean conscience, fully acceptable for entrance into the kingdom. I no longer have the WT library after a few crashes of my PC. My version was no. 8. If you look it up its there.
Found it on Google, lol:
However, there are two phases in the sealing of anointed ones. The
initial sealing differs from the final sealing (1) in purpose and (2) in
time. The sealing in an initial sense serves to select a new member who
is added to the number of anointed Christians. The sealing in a final
sense serves to confirm that this chosen and sealed individual has fully
demonstrated his loyalty. Only then, at the final sealing, will the
seal be permanently placed ‘in the forehead’ of the anointed one,
identifying him conclusively as a tried and faithful ‘slave of our God.’
The sealing mentioned in Revelation chapter 7 refers to this final phase of the sealing.—Revelation 7:3.
When will the remnant of anointed Christians who have initially been
sealed receive their final sealing? Any still alive on earth will be
sealed “in their foreheads” before the outbreak of the great
tribulation. When the four winds of tribulation are unleashed, all of
spiritual Israel will have been sealed in finality, even though a few
will still be alive in the flesh and must yet finish their earthly
course.