1 Kings 5:17 - Joseph Benson’s Commentary on the Old and New Testaments

Costly stones Marble and porphyry, or other stones of great size and value. To lay the foundation of the house Where they could not afterward be seen; and therefore that this was done, is mentioned only as a point of magnificence, except it was intended for a type or mystical signification of the preciousness of Christ, who is the foundation of the true temple, and the church of God. “It should seem,” says Henry, “that Solomon was himself present at the founding of the temple, and that the first stone, as has been usual in famous buildings, was laid with great solemnity. Solomon commanded, and they brought costly stones For a foundation; though, being out of sight, worse might have served. Christ, who is laid for a foundation, is an elect and precious stone, (Isaiah 28.,) and the foundations of the church are said to be laid with sapphires, Isaiah 54:11. and Revelation 21:19. Sincerity obligeth us to lay our foundation firm, and to bestow most pains on that part of our religion which lies out of the sight, of men.”