That I may show forth all thy praise
That is, all thy bounties and acts of goodness, deserving of praise; even as many of them as he had an experience of, and which came within his knowledge; and as much of them as he was capable of observing: for otherwise the instances of divine grace and goodness are so many, that they cannot be reckoned up in order, nor God be praised for them, in the present state of things, as he should; (See Gill on Psalms 9:1);
in the gates of the daughter of Zion:
it was usual with the Hebrews to represent a chief city as a mother city, and the towns and villages, and places adjacent, as daughters; and so, as Zion or Jerusalem signifies the church of God in general, or the mother church, ( Galatians 4:26 ) ; so "the daughter" of Zion may mean a particular church: the Targum renders it the congregation of Zion; and "the gates" of it are the public ordinances of divine worship in it; and the sense is, that the psalmist desired to show forth the praises of God in the most public manner in the congregation and assembly of the saints;
I will rejoice in thy salvation,
or "that I may rejoice in thy salvation" F13: meaning either temporal salvation and deliverance from enemies, wrought by God for him, which would be matter of joy to him; or spiritual salvation, which may be called God's salvation, because contrived by him in the council of peace, and secured by him in the covenant of grace, and wrought out by his Son in the fulness of time, and applied by his Spirit at conversion. And a gracious man rejoices in this salvation more because it is the Lord's than because it is his own; or he rejoices more because of the glory of God, which is displayed in it, than because of his own advantage and happiness by it.