O Lord, open thou my lips; and my mouth shall shew forth thy praise.
Ver. 15. O Lord, open thou my lips] Which now I find stopped and sealed up, as it were, with the sin that doth so easily beset me; so that whereas I promised before to "sing aloud of thy righteousness," this I shall never be able to do without thy special furtherance, nisi verba suppedites et tanquam praeeas, unless thou please to supply me both with affections and expressions, as well as with matter of praise.
And my mouth shall show forth thy praise] David had not been dumb till now, all the while he lay in his sin, but all he did was but liplabour, and therefore lost labour. Daniel confesseth the like of himself and his people, Daniel 9:13, "All this evil is come upon us: yet made we not our prayer before the Lord our God, that we might turn from our iniquities, and understand thy truth." Prayed they had, but because they turned not from their iniquities, they got nothing by their prayers or praises. God is a fountain, and if he meet with a fit pipe (as is an ordinance rightly performed), there he usually conveyeth his grace; but if he meet with a foul pipe and obstructed, there he doth not confer a blessing. The Pharisees were not a button the better for all their long prayers, because rotten at heart.