It isn't that He needs to know, but that we need to ask, because doing so places our expectation and hope where it belongs - in the One who has unassailable mastery over the living and the dead, and absolute rule over every act of every creature and every force of nature.
I understand what you are saying.
The Epistle of James was written to Jewish Christians, right? Were these Christians lusting and killing? What was God withholding from them until they asked? And don't they have to be obedient to God's commands in order to receive?
James 4:2 (King James Version)
2Ye lust, and have not: ye kill, and desire to have, and cannot obtain: ye fight and war, yet ye have not, because ye ask not.
1 John 3:21-22 (King James Version)
21Beloved, if our heart condemn us not, then have we confidence toward God.
22And whatsoever we ask, we receive of him, because we keep his commandments, and do those things that are pleasing in his sight.
