And David and the captains of the host appointed out to do service, the sons of Asaph of Heman and Jeduthun, which did prophesy with harps, psalteries and cymbals. And they were numbered unto the work according to their office.

And they set the Levites in the house of the LORD with cymbals, psalteries and harps according to the commandments of David and of Gad the king's seer of visions and of Nathan the prophet. For so was the commandment of the LORD through the hand, of his prophets.

And Hezekiah set the priests and the Levites in their order to wait by course, every man according to his office whether priest or Levite, for the burnt offerings and peace offerings, and to minister and to thank and to pray in the gates of the lodge of the LORD.

And when the builders laid the foundation of the temple of the LORD, the priests stood in their array, with trumpets, and the Levites, the children of Asaph, with cymbals; to praise the LORD, after the manner of David, king of Israel.

{Praise the Everlasting} O praise the name of the LORD! Praise it, O ye servants of the LORD;

We hanged our harps upon the salon-trees, in the midst of it.

And when he had taken the book, the four beasts and twenty four elders fell down before the lamb, having harps and golden vials full of odours, which are the prayers of saints,

And they sang as it were a new song, before the seat, and before the four beasts, and the elders and no man could learn that song, but the hundred and forty four thousand which were redeemed from the earth.

Every morning

the one thou shalt offer in the morning and the other at even.

{A Psalm of the song for the Sabbath Day} It is a good thing to give thanks unto the LORD, and to sing praises unto thy name, O most highest!

{A song of the stairs} Behold now, praise the LORD, all ye servants of the LORD, ye that by night stand in the house of the LORD.

General references

Should I use them to be porters of the house, and to all the service that is done therein?