פִּתְח֖וּ שְׁעָרִ֑ים וְיָבֹ֥א גוֹי־צַדִּ֖יק שֹׁמֵ֥ר אֱמֻנִֽים׃
Open ye the gates, That the righteous nation that keepeth faithfulness may enter in.
Ibn Ezra
Open ye gates, etc. The gates of that city should only be opened for righteous people like the Israelites, to enter and to dwell in it.
Rashi
awaiting, that waited and longed in its exile many days for the faith of the Holy One, blessed be He, that He fulfill His promise through His prophets, to redeem them.
Rashi
awaiting (שֹׁמֵר) waiting. Comp. (Gen. 37:11) “And his father awaited (שָׁמַר) the matter.” Similarly (Deut. 7:12), “And the Lord, your God, shall await (וְשָׁמַר) the covenant for you.”