'Myriads' in the Bible

and he saith: -- 'Jehovah from Sinai hath come, And hath risen from Seir for them; He hath shone from mount Paran, And hath come with myriads of holy ones; At His right hand are springs for them.

His honour is a firstling of his ox, And his horns are horns of a reem; By them peoples he doth push together To the ends of earth; And they are the myriads of Ephraim, And they are the thousands of Manasseh.