LXX Psalm 143:9
7 Send forth thine hand from on high; rescue me, and deliver me out of great waters, out of the hand of strange children; 8 whose mouth has spoken vanity, and their right hand is a right hand of iniquity. 9 O God, I will sing a new song to thee: I will play to thee on a psaltery of ten strings. 10 Even to him who gives salvation to kings: who redeems his servant David from the hurtful sword. 11 Deliver me, and rescue me from the hand of strange children, whose mouth has spoken vanity, and their right hand is a right hand of iniquity;
Psalms of Solomon 3:1
1 Why am I sleeping, and not praising the Lord? Strum a new song to God who is worthy to be praised. 2 Keep on strumming and keep awake for he is awake. For a good psalm to God comes from a good heart. 3 The Lord is on the mind of the righteous through everything by recognizing and proving that the Lord's judgments are right.
Notes and References
"... The singing of psalms was a prominent part of worship at the Second Temple, in relation to the daily and Sabbath cult and especially festival pilgrimage (Falk 1998: 194–9; e.g. 1 Chronicles 23:30– 31; 2 Chronicles 30:21; Sirach 47:9–10; 50:18; 1 Maccabees 4:52–59; 2 Maccabees 1:30; 10: 6–8; Philo, Special Laws 1.193–5). This involves formal performance by the Temple singers, but the use of refrains points to participation of pilgrims, and there are also references to popular singing by pilgrims, both at the Temple and on the way home. Other settings in which the singing of songs is attested include victory celebrations (e.g. 1 Maccabees 4:24; Josephus, Antiquities 12: 349) and festival celebrations at home (especially Passover seder: Philo, Laws 2:148; Josephus, Antiquities 2:346; compare Jubilees 49:6; Wisdom 18:9; Mark 14:26; see Bokser 1984). It is difficult to know whether the celebration of the Alexandrian community with singing of hymns on the beach at the news of the arrest of Flaccus (Philo, Flaccus 116–25) is to be understood as an eruption of spontaneous victory songs or as also reflective of festival celebration which normally would have (p. 634) taken place in their synagogue. There is also perhaps an allusion to psalms in Sabbath assembly (Psalms-Philo 11:8; but compare McKay 1994: 13), and to private songs in the morning (Psalms of Solomon 3:1–3; 6:4–5) ..."
Falk, Daniel K. "The Contribution of the Qumran Scrolls to the Study of Ancient Jewish Liturgy" in Lim, Timothy H., and John J. Collins (eds.) The Oxford Handbook of the Dead Sea Scrolls (pp. 1-25) Oxford University Press, 2010