1 Corinthians 14:21

Overview - 1 Corinthians 14
Prophecy is commended,
and preferred before speaking with tongues,
by a comparison drawn from musical instruments.
12 Both must be referred to edification,
22 as to their true and proper end.
26 The true use of each is taught,
27 and the abuse taxed.
34 Women are forbidden to speak in church.
Treasury of Scripture Knowledge

1 Corinthians 14:21  (King James Version)
In the law it is written, With men of other tongues and other lips will I speak unto this people; and yet for all that will they not hear me, saith the Lord.

the law
The passage quoted is taken from the prophet Isaiah; but the term torah, Law, was used by the Jews to express the whole Scriptures, law, prophets, and hagiographia; and they used it to distinguish these Sacred Writings from the words of the scribes
It is not taken from the LXX., from which it varies as much as any words can differ from others where the general meaning is similar. It accords much more with the Hebrew; and may be considered as a translation from it; "only what is said of God in the third person, in the Hebrew, is here expressed in the first person, with the addition of [lego
kurios ,"] saith the Lord--Dr. Randolph.
John 10:34 ; Romans 3:19

Deuteronomy 28:49 ; Isaiah 28:11 Isaiah 28:12 ; Jeremiah 5:15