The scene here is typical rather than unusual. Jesus raised His hands and then blessed the disciples. First it denotes an open hand rather than closed and conveys power, means and direction. The Hebrews incorporated this word into titles of worship or praise times. From the simple act of raising the hand in prayer or worship the Hebrews acknowledged that it was God they were extending the hand of fellowship, friendship and yes surrender.
Hands play an important part of worship.
Paul instructed his readers to lift Holy hands to God. They would have understood this as worship. Actually it is quite natural and right. No, but do not look down on those who do. When one is moved to recognize the Almighty, or is confronted with his own smallness do not be surprised if you suddenly see their hands, ever so slowly, raise up in total surrender.