A deep, internal desire to honor God carries immense spiritual weight, even before any physical action is taken. God communicates a profound message to David through a prophet, directly addressing the king's sincere wish to build the Temple. The focus rests entirely on David's inner thoughts and his genuine ambition to construct a house dedicated to God. In response, God expresses deep approval and appreciation for this royal initiative.
There is a broad agreement that David's noble thoughts and intentions were inherently good and worthy on their own. God fully validates this internal desire, confirming that He too chooses the exact house David envisioned as the place where His name will eventually dwell [רש״י]. Furthermore, this pure motivation stands as a massive credit to David. It was precisely his intense passion that sparked the practical preparations for the Temple and laid the groundwork for the future divine command regarding its actual construction [מצודת דוד].