Public or church prayer required by God, and the reasons why 6/8

As for the excellency of conceived prayer, wherein the devout Christian, out of the abundance of his heart, pours out his requests to God, none but a profane spirit dares open his mouth against it.  But is there no way to magnify the excellency of that but by vilifying and imputing sin to the other?  Alas! the evil is not in a form, but in formality; and that is a disease that may be found in him that prays with a conceived prayer.  A man may pray without a form and yet not pray without formality.  Though I confess he that binds himself constantly to a set form—especially in his private addresses—seems to me to be more in danger of the two, to fall under the power of that lazy distemper.  But to hasten the despatch of this question—for I intend not a full discourse of this point, but would top a few heads only, which you may find more largely insisted on in many worthy treatises on this subject—I would desire those that scruple the lawfulness of all set forms, to look wishly upon those set forms of blessing, prayers, and thanksgiving that are upon scripture record, and were used by the servants of God with his approbation, and then consider whether God would prescribe or accept what is unlawful.  The priests had a form of blessing the people, Num. 6:24.  Moses used, as I hinted, a form of prayer at the remove of the ark, ‘Rise up, Lord, and let thine enemies be scattered; and let them that hate thee flee before thee;’ and when it was set down another form, ‘Return, O Lord, unto the many thousands of Israel,’ Num. 10:36, which very form was continued and used by David, Ps. 68:1.  Asaph and his brethren had set forms of thanksgiving given them to use in their public service, ‘Then on that day David delivered first this psalm to thank the Lord into the hand of Asaph and his brethren,’ I Chr. 16:7.  This was the first appointed to be sung in the public service; the several parts thereof were afterwards much enlarged, as you may see by comparing Ps. 105 with the former part of the song in the place fore quoted, and Ps. 96, with the latter part of it.  At the dedication of the temple, Solomon used the very form of words in praising God which his father had penned, II Chr. 7:6.  Good Hezekiah commands the Levites ‘to sing praise unto the Lord with the words of David,’ II Chr. 29:30.  This holy man no doubt was able to have poured forth extemporary praises, as it is thought he did in that prayer which he on the sudden, put up on the occasion of that railing letter sent him, II Kings 19:14; yet did not think it unlawful to use a form in his public administration.  Yea, our blessed Saviour—an instance beyond all instances—both gave a form of prayer to his disciples, and himself disdained not to pray three several times one after another the very same form of words, ‘He left them, and went away again, and prayed the third time, saying the same words,’ Matt. 26:44.  And that hymn which he sang with his disciples is conceived by the learned to be that portion of psalms which the Jews used at the celebration of the passover.  (See Beza and Gerhard, Harmo, in locum.)