Revelation 9 15
The four angels who had been kept ready for this particular hour, day, month and year were released to kill one third of humanity.
Compare with other 3 random translations
EAS Revelation 9:15So the four angels now became free. God had kept them ready for that special time, for that hour, in that day, in that month, in that year. They were now ready to kill a third of people everywhere.
KJV Revelation 9:15And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men.
AMP Revelation 9:15So the four angels who had been in readiness for that hour in the appointed day, month, and year were liberated to destroy a third of mankind.