And he set up the two pillars in the porch of the temple: and when he had set up the pillar on the right hand, he called the name thereof Jachin: in like manner he set up the second pillar, and called the name thereof Booz.

And he raiseth up the pillars for the porch of the temple, and he raiseth up the right pillar, and calleth its name Jachin, and he raiseth up the left pillar, and calleth its name Boaz;

He put up the pillars at the doorway of the Temple, naming the one on the right Jachin, and that on the left Boaz.

And he stationed the two columns in the portico of the temple. And when he had stationed the column on the right, he called its name Jachin. Similarly, he erected the second column, and he called its name Boaz.

The Septuagint in the parallel passage (margin reference), translate Jachin and Boaz by Κατόρθωσις Katorthōsis and Ἰσχύς Ischus - "Direction" and "Strength." The literal meaning of the names is given in the margin. The meaning was probably "God will establish in strength" (i. e. firmly) the temple and the religion connected with it.

The right pillar - Jachin - That is, He shall establish. The left pillar - Boaz, that is, in strength. These were no doubt emblematical; for notwithstanding their names, they seem to have supported no part of the building.

And he set up the pillars in the (l) porch of the temple: and he set up the right pillar, and called the name thereof (m) Jachin: and he set up the left pillar, and called the name thereof (n) Boaz.
(l) Which was in the inner court between the temple and the oracle.
(m) That is, he will stablish, that is, his promise toward this house.
(n) That is, in strength: meaning the power of it will continue.

And he set up the pillars in the porch of the temple,.... Not at the door or entrance into the temple, as Jarchi, but at the entrance into the porch:
and he set up the right pillar; or the pillar on the right hand as you went in, which was on the north, the front being east:
and called the name thereof Jachin; which signifies "he will establish", i.e. the house to which here was an entrance, so long as the pure worship of God should continue in it:
and he set up the left pillar; or the pillar on the left hand, which was to the south, unless the position of them was as you come out:
and called the name thereof Boaz; which signifies "in him", or "it is strength", namely, in the Lord that dwelt there; for this has no respect to Boaz, a prince of the house of Judah, from whom all its kings sprung, as the Targum, in 2-Chronicles 3:17 suggests. These names were given them not by Hiram the artificer, but by Solomon, and which were very expressive; not so much of the nobility of the kingdom of the house of David, as the Targum intimates; or of the church of God, the pillar and ground of truth; as of Christ himself, and the two natures in him, and of his royal dignity, signified by the crowns or chapiters on them, decorated as they were, whose legs are as pillars of marble, and in whom are righteousness and strength; which is no small encouragement to those who are entering into the church of God the temple was a type of; who, should they fear, being feeble and weak, that they should totter and fall, here stands Jachin, to let them know the Lord will establish and settle them; or that they should never hold out to the end, here is Boaz to direct them to Christ, in whom their strength lies, see Song 4:15. Allusion is had to these, Revelation 3:12.

Jachin and . . . Boaz--These names were symbolical, and indicated the strength and stability--not so much of the material temple, for they were destroyed along with it (Jeremiah 52:17), as of the spiritual kingdom of God, which was embodied in the temple.

"And he set up the pillars at the hall of the Holy Place, and set up the right pillar, and called its name Jachin, and the left...Boaz." Instead of ההיכל לאוּלם we have in 2-Chronicles 3:15 הבּית לפני, and in 2-Chronicles 3:17 ההיכל על־פּני, "before the house," "before the Holy Place." This unquestionably implies that the two brazen pillars stood unconnected in front of the hall, on the right and left sides of it, and not within the hall as supporters of the roof. Nevertheless many have decided in favour of the latter view. But of the four arguments used by Thenius in proof that this was the position of the pillars, there is no force whatever in the first, which is founded upon Amos 9:1, unless we assume, as Merz and others do, that the words of the prophet, "Smite the capital, that the thresholds may shake, and break them (the capitals of the pillars), that they may fall upon the head of all," refer to the temple at Jerusalem, and not, as Thenius and others suppose, to the temple erected at Bethel for the calf-worship. For even if the temple at Bethel had really had a portal supported by pillars, it would by no means follow that the pillars Jachin and Boaz in Solomon's temple supported the roof of the hall, as it is nowhere stated that the temple of Jeroboam at Bethel was an exact copy of that of Solomon. And even with the only correct interpretation, in which the words of Amos are made to refer to the temple at Jerusalem, the argument founded upon them in support of the position of the pillars as bearers of the hall rests upon the false idea, that the ספּים, which are shaken by the smiting of the capital, are the beams lying upon the top of the pillars, or the superliminaria of the hall. It is impossible to prove that סף has any such meaning. The beam over the entrance, or upon the doorposts, is called משׁקוף in Exodus 12:7, Exodus 12:22-23, whereas סף denotes the threshold, i.e., the lower part of the framework of the door, as is evident from Judges 19:27. The words of the prophet are not to be interpreted architecturally, but to be taken in a rhetorical sense; "so that by the blow, which strikes the capital, and causes the thresholds to tremble, such a blow is intended as shakes the temple in all its joints" (Baur on Amos 9:1). "הכּפתּור, a kind of ornament at the top of the pillars, and הסּפּים, the thresholds, are opposed to one another, to express the thought that the building is to be shaken and destroyed a summo usque ad imum, a capite ad calcem" (Hengstenberg, Chrisol. i. p. 366 transl.). The other arguments derived from Ezekiel 40:48 and Ezekiel 40:49, and from Josephus, Ant. viii. 3, 4, prove nothing at all. From the words of Josephus, τούτων τῶν κιόνων τὸν μέν ἕτερον κατὰ τὴν δεξιὰν ἔστησε τοῦ προπυλαίου παραστάδα...τὸν δὲ ἕτερον κ.τ.λ., it would only follow "that the pillars (according to the view of Josephus) must have stood in the doorway," if it were the case that παραστάς had no other meaning than doorpost, and προπύλαιον could be understood as referring to the temple-hall generally. But this is conclusively disproved by the fact that Josephus always calls the temple-hall πρόναον (l.c., and viii. 3, 2 and 3), so that προπύλαιον can only denote the fore-court, and παραστάς a pillar standing by itself. Consequently Josephus regarded the pillars Jachin and Boaz as propylaea erected in front of the hall. We must therefore adhere to the view expressed by Bhr (d. Tempel, p. 35ff.), that these pillars did not support the roof of the temple-hall, but were set up in front of the hall on either side of the entrance. In addition to the words of the text, this conclusion is sustained (1) by the circumstance that the two pillars are not mentioned in connection with the building of the temple and the hall, but are referred to for the first time here in the enumeration of the sacred vessels of the court that were made of brass. "If the pillars had formed an essential part of the construction and had been supporters of the hall, they would certainly have been mentioned in the description of the building, and not have been placed among the articles of furniture" (Schnaase); and moreover they would not have been made of metal like the rest of the vessels, but would have been constructed of the same building materials as the hall and the house, namely, of stone or wood (Bhr). And to this we may add (2) the monumental character of the pillars, which is evident from the names given to them. No architectural portion of the building received a special name.
(Note: Stieglitz (Gesch. der Baukunst, p. 127) aptly observes in relation to this: "The architect cannot subscribe to Meyer's view (that the pillars were supporters of the hall), since it was only through their independent position that the pillars received the solemn character intended to be given to them, and by their dignity subserved the end designed, of exalting the whole building and calling attention to the real purpose of the whole.")
Jachin (יכין): "he establishes," stabiliet templum (Simonis Onom. p. 430); and Boaz (בּעז), ex עז בּו in illo, sc. Domino, robur (Sim. p. 460). Kimchi has correctly interpreted the first name thus: "Let this temple stand for ever;" and the second, "Solomon desired that God would give it strength and endurance." The pillars were symbols of the stability and strength, which not only the temple as an outward building, but the kingdom of God in Israel as embodied in the temple, received from the Lord, who had chosen the temple to be His dwelling-place in the midst of His people.
(Note: There is no necessity to refute the fanciful notion of Ewald, that these pillars, "when they were erected and consecrated, were certainly named after men who were held in estimation at that time, probably after the younger sons of Solomon," and that of Thenius, that בּעז יכין, "He (the Lord) establishes with strength," was engraved upon them as an inscription.)

Jachin - Jachin signifies he; That is, God shall establish, his temple, and church, and people: and Boaz signifies, in it, or rather, in him (to answer the he in the former name) is strength. So these pillars being eminently strong and stable, were types of that strength which was in God, and would be put forth by God for the defending and establishing of his temple and people, if they were careful to keep the conditions required by God on their parts.