Albert Barnes Commentary 1 Samuel 30:12

"And they gave him a piece of a cake of figs, and two clusters of raisins: and when he had eaten, his spirit came again to him; for he had eaten no bread, nor drunk any water, three days and three nights." — 1 Samuel 30:12 (ASV)

Three days and three nights — This indicates that at least this much time had passed since the sack of Ziklag.