In the porch of the temple; where they were placed for mere ornament and magnificence, for they supported nothing. Jachin signifies he, i.e. God, shall establish, to wit, 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 in a manner types or documents 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.
Related Commentaries of 1 Kings 7:21
1 Kings 7:21
21 And he set up the pillars in the porch of the temple: and he set up the right pillar, and called the name thereof Jachin:h and he set up the left pillar, and called the name thereof Boaz.