Isaiah 41:7

וַיְחַזֵּק חָרָשׁ אֶת־צֹרֵף מַחֲלִיק פַּטִּישׁ אֶת־הוֹלֶם פָּעַם אֹמֵר לַדֶּבֶק טוֹב הוּא וַיְחַזְּקֵהוּ בְמַסְמְרִים לֹא יִמּוֹט׃

7 The craftsman encourages the smith, and the one who smooths with the hammer [encourages] the one who strikes the anvil, saying to his detailed metalwork, "It is good." He nails it down with nails so that it can't topple.

In verses 1-6, God convened a court as he often does in the prophets, and asked the tough questions, the "Job" questions -- where were you when I made the universe? Who is the one who made everything? Who is the one who stirred up the "one" in the east, the "one" who will cause all of you to tremble? Now Isaiah tells us how some of the people answer the tough questions. They hack away at a block of wood and they worship it.

וַיְחַזֵּק חָרָשׁ אֶת־צֹרֵף The craftsman encourages the smith,  חָרָשׁ is a simple noun, and although some lexicons present "artificer" or "graver" as a definition, "smith" or "blacksmith" is what were talking about. Craftsman allows the idea of "woodworker" in the minds of our people, but in this verse, a beaten lump of metal on an anvil is the object, and a huge bemuscled blacksmith is the most obvious image. Of course, the problem is that צֹרֵף also means "smith," and we are left with the impression that Isaiah just never had many good things to say about their profession. וַיְחַזֵּק is a piel waw-consecutive imperfect, "make firm, encourage." The Mp note says that וַיְחַזֵּק occurs five times, and the every time when it is closely followed by the Tetragrammaton is like this. The five are 1 Sam 23:16; Isaiah 41:7; Neh. 3:19; 2 Chron 11:11 and 32:5. Cases where it is followed by יהוה include Exodus 9:12; 10:20; 10:27; 11:10; 14:8; and Judges 3:12. Another Mp note shows that צֹרֵף occurs four times written defectively. See Isaiah 40:19 notes for the list.

מַחֲלִיק פַּטִּישׁ אֶת־הוֹלֶם פָּעַם and the one who smooths with the hammer [encourages] the one who strikes the anvil,  מַחֲלִיק is a hifil participle from חָלַק, "smooths." Another Mp note points out that מַחֲלִיק occurs twice (cf. Prov. 29:5, "Whoever flatters [i.e. makes smooth] his neighbor is spreading a net..."). In Greek we would call פַּטִּישׁ ("hammer") a dative of instrument. Here the accent combination of tebir and tipha joins the words into a unified phrase, "The hammer-smoother." I always think the word for hammer (פַּטִּישׁ) sounds like a hammer breaking a pane of glass. Another Mp note says that פַּטִּישׁ occurs twice: "How the hammer of the whole earth is broken and shattered!" Jer. 50:23. The qal participle הוֹלֶם is the object of the understood verb "encourages" which is not present in the phrase but the verb shared through parallelism with the first phrase. פָּעַם "anvil" is the object of the "striking."

אֹמֵר לַדֶּבֶק טוֹב הוּא saying to his detailed metalwork, "It is good."  דֶּבֶק is a hard word to put into modern terms. I think that "joinery," a word I strongly considered, is just silly. But "welding" or "soldering" is a modern invention, and not what Isaiah meant. I can't bring myself to use a word like "filigree," and "metalworking" or "detailed metalwork" is the best I can come up with. It's only other occurrences are in 1 Kings 22:34 and 2 Chronicles 18:33. Once again הוּא is virtually a verb.

וַיְחַזְּקֵהוּ בְמַסְמְרִים לֹא יִמּוֹט He nails it down with nails so that it can't topple. וַיְחַזְּקֵהוּ piel waw-consec imperfect חָזַק. The "nails" מַסְמְרִים are prefixed by a -בְּ of manner. The form מַסְמְרִים is a hapax legomenon; this word is so rare that it occurs equally with a masculine and feminine plural ending. Isaiah choice of יִמּוֹט (nifal imf מוֹט) is an inspired turn of phrase (I'm speaking figuratively and literally, of course) being so close to the sound of מוֹת "dead," which is what an idol is.

Notice what they say as they admire the work of their own hands and their own evil creation. They look at their welding and they say "It is good." This is exactly what God said about his creation when he made the world out of nothing. God saw that what he had made was truly good; these craftsmen have to talk each other into it, and they only reinforce their sins.