I believe that this hymn is building on the Jewish ritual for the Day of Atonement. In the Day of Atonement, one element after the priest has laid his hands on the scapegoat and confessed the sins of the people, he would pronounce forgiveness for the nation. Within this pronouncement, the high priest would speak the divine name. At the mention of the divine name, the people would fall down and praise his name. There are quite a few connections between Philippians 2 and the details of Yom Kippur.
And the priests and the people standing in the courtyard, when they would hear God’s name explicated coming out of the high priest’s mouth, would bend their knees, bow down and fall on their faces and say “Blessed be the name of His glorious kingdom for ever and ever!
Shared Elements between Hymn and Mishnah
- The pronunciation of the name
- Response of bending the knee
- Response of praising the name
Therefore, it appears that Paul is reframing this ritual around Jesus' death and resurrection. You can see that both depictions share multiple elements. However, in this depiction, Jesus is receiving the praises that were previously directed towards God. If this be the case, the name mentioned is the divine name, YHWH. Paul is presenting Jesus as an atoning sacrifice (Phil. 2:6-8) and as God who forgives, who is worthy of worship (Phil. 2:9-11).