Nehemiah 8:6

And Ezra blessed the Lord, the great God
Before he began to read in the book of the law, he addressed himself to God in a short prayer, wholly in the benedictory way; ascribing blessing, honour, and glory to him, celebrating his being and perfections, setting forth his greatness and his excellency, who was the author and giver of the law he was about to read; and this he the rather did, that what he read might be the more carefully attended to, and come with the greater authority, weight, and influence on those that heard it; and so, Maimonides ^F15 says, it is the custom with the Jews, in their synagogues, for the reader, after he has opened the book, and looked out the place he reads, to say this blessing,

``Blessed art thou, O Lord our God, King of the world, who hath chosen us out of all people, and hath given us his law; blessed art thou, O Lord, who hast given us the law; and all the people answer, Amen;''

and all the people answered, Amen, Amen:
repeating the word, to declare their hearty assent to what Ezra had expressed; the Jews have many rules concerning pronouncing the "Amen", that it must not be too quick, curt, and short, nor with too high a voice ^F16:

with lifting up their hands;
a prayer gesture, to which the apostle refers, ( 1 Timothy 2:8 ) ,

and they bowed their heads, and worshipped the Lord with their faces to
the ground;
expressing hereby the awful sense they had of the Divine Being, and their profound adoration of him.