Charles Ellicott Commentary Proverbs 17:3

"The refining pot is for silver, and the furnace for gold; But Jehovah trieth the hearts." — Proverbs 17:3 (ASV)

The fining pot is for silver. — See above on Proverbs 2:4.

The Lord tries the hearts. — By allowing sorrows and temptations to assail them, in order that they may come out of the trial as pure gold (Revelation 3:18; 1 Peter 1:7; 1 Corinthians 3:13; Malachi 3:3), purged of earthly infirmities.