Three days after His crucifixion “the disciples became assured and steadfast, … began to serve the Cause of Christ” and as a result “the Reality of Christ became resplendent and His bounty appeared”

...The Cause of Christ was like a lifeless body; and when after three days the disciples became assured and steadfast, and began to serve the Cause of Christ, and resolved to spread the divine teachings, putting His counsels into practice, and arising to serve Him, the Reality of Christ became resplendent and His bounty appeared; His religion found life; His teachings and His admonitions became evident and visible. In other words, the Cause of Christ was like a lifeless body until the life and the bounty of the Holy Spirit surrounded it.

Such is the meaning of the resurrection of Christ, and this was a true resurrection....
- ‘Abdu’l-Baha  (‘Some Answered Questions')

Meeting of Christ with the apostles after His crucifixion

...Thou hast written concerning the meeting of His Highness Christ after the crucifixion and that some of the apostles perceived Him but did not recognize Him; but that they did recognize Him after the breaking of bread.

Know thou that the Messianic Spirit and the outpouring of the Holy Spirit is always manifest, but capacity and ability (to receive it) is more in some and less in others. After the crucifixion the apostles had not in the beginning the capacity and ability of witnessing the Messianic reality. For they were agitated. But when they found firmness and steadfastness, their inner sight became opened, and they saw the reality of the Messiah as manifest. For the body of Christ was crucified and vanished, but the Spirit of Christ is always pouring upon the contingent world, and is manifest before the insight of the people of assurance. 
- ‘Abdu’l-Baha  (Tablets of Abdul-Baha, Vol. 1)