After David had purchased the land upon which to build a temple, he began collecting supplies for the construction of it. He wasn't going to be allowed to build it himself, but God accepted his desire to help prepare for the project... a project which his son Solomon would undertake.
According to this chapter, David gathered stones, iron, brass, cedar, gold and silver to make the house of God "exceeding magnifical" - really, especially and superbly wonderful. David wanted God's house to be extravagant. He was planning for it. He stocked warehouses with materials and even enlisted teams of talented specialists to prepare for the project (1st Chronicles 22:15). And, he charged his royal court to help his son when the work commenced (1st Chronicles 22:17). But, above all else he instructed his son to live by faith; to seek God's face; to study His Word. David knew that no amount of planning or diligent effort would suffice without God's blessings.