In v.7, she related the details of the prophecy. He believed his wife, but he didn't know what to do. He was not motivated by curiosity but by commitment. Of course, he hears every word we speak and knows all our thoughts, but how precious to know that His greatest interest is in our prayers. Imagine her as she found Manoah.
Men are so logical.
He didn't waste time with emotions but wanted to verify the Messenger's identity. He was momentarily overwhelmed. His faith in his wife's testimony and his prayers to the Lord had been validated. Manoah got right to the point. He wanted to know what He should do as the father of a deliverer.