Revelation 11:6

These have power to shut heaven so that it does not rain 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.

Luke 4:25

In very truth I tell you there were many widows in Israel in the days of Elijah, when the heavens were closed for three years and six months, when a great famine came over all the land;

James 5:16-18

So confess your sins one to another, and pray for one another, that you may be healed. For the fervent prayer of a righteous man is mighty in its working.

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
In very truth I tell you there were many widows in Israel in the days of Elijah, when the heavens were closed for three years and six months, when a great famine came over all the land;
James 5:16
So confess your sins one to another, and pray for one another, that you may be healed. For the fervent prayer of a righteous man is mighty in its working.