Charles Ellicott Commentary Ezra 6:3

"In the first year of Cyrus the king, Cyrus the king made a decree: Concerning the house of God at Jerusalem, let the house be builded, the place where they offer sacrifices, and let the foundations thereof be strongly laid; the height thereof threescore cubits, and the breadth thereof threescore cubits;" — Ezra 6:3 (ASV)

Strongly laid. — Thy foundation shall be laid (Isaiah 44:28). The decree adds a word that signifies "with sufficient support."