There were times and places where Popes and Patriarchs declined to convey episkope to a candidate unable to recite the whole Psalter memoriter. It remains true that not very many of us could deliver very many of the psalms from memory. Perhaps some of us could repeat just one psalm perfectly; partly because it consists of but two verses; partly because it is the psalm which concludes Traditional Sunday Evening public worship, being by custom the concluding element in the service of Benediction as it commonly was done in this Atlantic Archipelago.
Byzantine Christians may be familiar with ps 116/117 as the last of the psalms in the Saturday Vespers with which Byzantines begin the celebration of the Lord's Day. Really elderly Latins might recall that right at the end of the Easter Vigil, as it was celebrated in those far off days before Bugnini got to work, this was the psalm of the vestigial First Vespers of Easter with which that service concluded. It is a not inept summary of the Paschal Mystery.
It opens with one of the commonest words in the psalter: HLLU. Most will recognise this as the command which is often combined with an abbreviated form of the Tetragrammaton to give us the form HLLU-YA (Hallelujah; Alleluia). And a browse through the three columns in Brown Driver and Briggs suggests that this is noisy word; with suggestions of shouting or crying aloud as you might at a wedding feast or a harvest thanksgiving. The context is commonly liturgical. But in this psalm the text proceeds rather unusually: HLLU ET-YHWH KL GOIM means "Praise YHWH all Gentiles". It is not common to find a term which is most at home with the chosen people as they worship God in the exclusivity of their Temple being applied to the unclean Gentiles beyond the Soreg. Not surprisingly, the Rabbi from Tarsus, whose festival we celebrate today, refers this to the eschatological glorifying of God for His mercy by the Gentiles; in which his teaching is in the rabbinic mainstream (cf R. Kimchi "This psalm ... belongs to the days of the Messiah ... the Gentiles shall worship YHWH") except for the fact that S Paul believes this part of the Eschaton to be even now fulfilled.
S Paul and other rabbis are confident that the psalm's next phrase refers to the peoples, or tribes, of 'the Circumcision'. But the verb here is a different one: ShBCh, which is very much less common (BDB call it a late Aramaism); some have felt that it lacks the exuberance of HLL. The various Greek and Latin manuscripts and editions are uncertain how to bring out the difference - they tend to use the same Greek (ain-) or Latin (laud-) roots, sometimes adding prefixes such as ep- and col- (although Pius XII's chum Cardinal Bea experimented with praedicate) which suggest 'in accompaniment'. It almost looks as though the Hebrew Nation is being given a supporting role in the Gentile liturgical praise of YHWH! But no.
Pauline theology enables us to tie things in together. It is in the Paschal Blood of Christ, in His Easter Flesh, that the Temple's middle wall of partition is broken down and the Both, Jew and Gentile, are reconciled in one Body to God through the Cross. As the Messiah dies upon the Cross, the Veil of the Temple is torn in two and the Enmity is itself killed. It is in this way that Christ became a servant of the Circumcision on behalf of the Truth of God to confirm the Promises of the Fathers. And He confirmed those promises by fulfilling them, He the Antitype to their types. As we sang earlier in Benediction, Et antiquum documentum novo cedat ritui.
So indeed, the truth of the LORD endureth for ever.