Isaiah 5:12

5:12 They have stringed instruments, ¹  tambourines, flutes,

and wine at their parties.

So they do not recognize what the Lord is doing,

they do not perceive what he is bringing about. ² 

Isaiah 30:29

30:29 You will sing

as you do in the evening when you are celebrating a festival.

You will be happy like one who plays a flute

as he goes to the mountain of the Lord, the Rock who shelters Israel. ³ 

[5:12]  ¹ tn Two types of stringed instruments are specifically mentioned in the Hebrew text, the כִּנּוֹר (kinnor, “zither”) and נֶבֶל (nevel, “harp”).

[5:12]  ² tn Heb “the work of the Lord they do not look at, and the work of his hands they do not see.” God’s “work” can sometimes be his creative deeds, but in this context it is the judgment that he is planning to bring upon his people (cf. vv. 19, 26; 10:12; 28:21).

[30:29]  ³ tn Heb “[you will have] joy of heart, like the one going with a flute to enter the mountain of the Lord to the Rock of Israel.” The image here is not a foundational rock, but a rocky cliff where people could hide for protection (for example, the fortress of Masada).