The answer
The Lord Jesus Christ is Almighty God. He is above time and space. He fills the heavens and the earth and everything in them. The Holy Scripture does not indicate the exact time and day of when our Lord met with His disciples in Galilee. Actually, our Lord Jesus Christ met with His disciples and apostles at various times and locations after His resurrection. The meeting in Galilee had a special meaning to the disciples, and thus, when the women proclaimed this specific location, it sparked the disciples' memory regarding His identity and His resurrection—not that He would meet them that specific day. The Lord did in fact meet with His disciples in Galilee, but at a different time—not specified. He appeared to His disciples in the upper room on the actual day of His resurrection when St. Thomas was not present. He later met with other disciples and apostles on the road to Emmaus and with some by the Sea of Tiberius.Reference:
http://biblehub.com/commentaries/matthew/28-16.htm
Answered by His Eminence Metropolitan Youssef (opens in a new tab)