hIn this context, the Hebrew expressions tsaw-tsaw and qaw-qaw are likely meant to sound like baby talk, but they could mean “command upon command” and “rule upon rule”
iLiterally “stammer of lip”
jOr “and”

In other versions

ESVEnglish Standard Version

“To whom will he teach knowledge,

and to whom will he explain the message?

Those who are weaned from the milk,

those taken from the breast?

For it is precept upon precept, precept upon precept,

line upon line, line upon line,

here a little, there a little.”

For by people of strange lips

and with a foreign tongue

the Lord will speak to this people,

to whom he has said,

“This is rest;

give rest to the weary;

and this is repose”;

yet they would not hear.

NIVNew International Version (2011)

“Who is it he is trying to teach?

To whom is he explaining his message?

To children weaned from their milk,

to those just taken from the breast?

For it is:

Do this, do that,

a rule for this, a rule for that;

a little here, a little there.”

Very well then, with foreign lips and strange tongues

God will speak to this people,

to whom he said,

“This is the resting place, let the weary rest”;

and, “This is the place of repose”—

but they would not listen.

CSBChristian Standard Bible

Who is he trying to teach?

Who is he trying to instruct?

Infants just weaned from milk?

Babies removed from the breast?

“Law after law, law after law,

line after line, line after line,

a little here, a little there.”

For he will speak to this people

with stammering speech

and in a foreign language.

He had said to them,

“This is the place of rest;

let the weary rest;

this is the place of repose.”

But they would not listen.

NLTNew Living Translation

“Who does the Lord think we are?” they ask.

“Why does he speak to us like this?

Are we little children,

just recently weaned?

He tells us everything over and over—

one line at a time,

a little here,

and a little there!”

So now God will have to speak to his people

through foreign oppressors who speak a strange language!

God has told his people,

“Here is a place of rest;

let the weary rest here.

This is a place of quiet rest.”

But they would not listen.

KJV 1900King James Version

Whom shall he teach knowledge?

And whom shall he make to understand doctrine?

Them that are weaned from the milk,

And drawn from the breasts.

For precept must be upon precept, precept upon precept;

Line upon line, line upon line;

Here a little, and there a little:

For with stammering lips and another tongue

Will he speak to this people.

To whom he said,

This is the rest wherewith ye may cause the weary to rest;

And this is the refreshing: yet they would not hear.

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