'Usher' in the Bible

Ask for rain from the Lord at the time of the spring rain.It is the Lord who makes the thunder clouds;And He will give them showers of rain, grass in the field to everyone.

The sun shall be turned into darkness and the moon into blood, to usher in the day of the Lord-- that great and illustrious day;

to usher in the fullness of the times and to bring together in the Messiah all things in heaven and on earth.