Srimad-Bhagavatam - Canto 2 Chapter 5 Text 3
sarvam hy etad bhavan veda
sarvam -- all and everything; hi -- certainly; etat -- this; bhavan -- your good self; veda -- know; bhuta -- all that is created or born; bhavya -- all that will be created or born; bhavat -- all that is being created; prabhuh -- you, the master of everything; kara-amalaka-vat -- just like a walnut within your grip; visvam -- the universe; vijnana-avasitam -- within your knowledge scientifically; tava -- your.
My dear father, all this is known to you scientifically because whatever was created in the past, whatever will be created in the future, or whatever is being created at present, as well as everything within the universe, is within your grip, just like a walnut.
Brahma is the direct creator of the manifested universe and everything within the universe. He therefore knows what happened in the past, what will happen in the future, and what is happening at present. Three principal items, namely the living being, the phenomenal world and the controller, are all in continuous action -- past, present and future -- and the direct manager is supposed to know everything of such actions and reactions, as one knows about a walnut within the grip of one's palm. The direct manufacturer of a particular thing is supposed to know how he learned the art of manufacturing, where he got the ingredients, how he set it up and how the products in the manufacturing process are being turned out. Because Brahma is the firstborn living being, naturally he is supposed to know everything about creative functions.