Sirach 50:20
Ben Sira, Ecclesiasticus18 Then the singers praised him with their voices in sweet and full-toned melody. 19 And the people of the Lord Most High offered their prayers before the Merciful One, until the order of worship of the Lord was ended, and they completed his ritual. 20 Then Simon came down and raised his hands over the whole congregation of Israelites, to pronounce the blessing of the Lord with his lips, and to glory in his name; 21 and they bowed down in worship a second time, to receive the blessing from the Most High. 22 And now bless the God of all, who everywhere works great wonders, who fosters our growth from birth, and deals with us according to his mercy. 23 May he give us gladness of heart, and may there be peace in our days in Israel, as in the days of old.
Luke 24:50
48 You are witnesses of these things. 49 And look, I am sending you what my Father promised. But stay in the city until you have been clothed with power from on high.” 50 Then Jesus led them out as far as Bethany, and lifting up his hands, he blessed them. 51 Now during the blessing he departed and was taken up into heaven. 52 So they worshiped him and returned to Jerusalem with great joy, 53 and were continually in the temple courts blessing God.
Notes and References
"... Luke does theology by creating a narrative with striking images and tableaus, invariably with first testament motifs. Surely, a high point in the gospel narrative is Jesus' ascension. As Jesus ascends, Luke depicts him giving Aaron's blessing as the high priest would after sacrifice on the Feast of Atonement. The sacrificial and expiatory interpretation of the cup connects with the Lucan running allusion to Sirach 50, where the glory and function of the high priest in the liturgy of the Day of Atonement are magnified. From Luke 9:31 through 24:53 one finds applied to Jesus words which in Sirach 50 refer to the officiating high priest and to the worshiping assembly. In Luke 22:14-23 and 24:50-53 Jesus is thus depicted functioning as a priest. The bread as memorial and the cup as the token of the covenant in Jesus' blood lay the narrative base for depicting the ascending Jesus completing the liturgy of the Day of Atonement. Jesus' giving the cup as new covenant in his blood and imparting Aaron's blessing bring narratively to full view Luke's image of Jesus' relation to the temple. With this image the Third Evangelist explores the meaning and significance of Jesus' relation to God and to people. The result may help us integrate the conflict in Luke with that in Acts. Jesus is the cornerstone which the chief priests, as the builders, rejected (Acts 4:11). Luke portrays Jesus subsuming in himself the worship associated with the temple ..."
Carpinelli, Francis G. ‘Do This as My Memorial’: Lucan Soteriology of Atonement (pp. 74-91) The Catholic Bible Quarterly 61, No. 1, 1999