John 11:9

In the day (th hmera). Genitive of time, within the day, the twelve-hour day in contrast with night. The words of Jesus here illustrate what he had said in 9:4 . It is not blind fatalism that Jesus proclaims, but the opposite of cowardice. He has full confidence in the Father s purpose about his "hour" which has not yet come. Jesus has courage to face his enemies again to do the Father's will about Lazarus. If a man walk in the day (ean ti peripath en th hmerai). Condition of the third class, a conceived case and it applies to Jesus who walks in the full glare of noonday. See 8:12 for the contrast between walking in the light and in the dark. He stumbleth not (ou proskoptei). He does not cut (or bump) against this or that obstacle, for he can see. Koptw is to cut and pros, against.