Revelation 11:6

during their prophecy they have power to prevent any rain descending from heaven: their power extends over waters to turn them to blood, and to smite the earth with what plagues they please.

Luke 4:25

I assure you, though there were many widows in Israel, when the heaven had furnished no rain for three years and a half, and a great famine spread through all the land:

James 5:16-18

confess then to one another the offences you have committed, and pray for one another, that you may be healed; the fervent prayer of a virtuous man has great influence.

Treasury of Scripture Knowledge

Summary

These have power to shut heaven, that it rain not in the days of their prophecy: and have power over waters to turn them to blood, and to smite the earth with all plagues, as often as they will.

Bible References

Power

Luke 4:25
I assure you, though there were many widows in Israel, when the heaven had furnished no rain for three years and a half, and a great famine spread through all the land:
James 5:16
confess then to one another the offences you have committed, and pray for one another, that you may be healed; the fervent prayer of a virtuous man has great influence.