In most cases, the meaning of "before" is pretty straightforward, both as a way of assessing relative time, and in its use meaning "in someone's presence." It takes on a deeper significance, though, when used in connection with the Lord. To be "before" the Lord means not just in His presence, but also receiving the desire for good and the understanding of truth from Him, and living according to them. And when used as an assessment of time in connection with the Lord, "before" means "from eternity," and refers to a spiritual state rather than time as we experience it.

(références: Apocalypse Revealed 366, 617; Arcana Coelestia 6983, 8439, 9888)

617. 14:3 They sang as it were a new song before the throne, before the four living creatures, and before the elders. This symbolizes a celebration and glorification of the Lord in His presence and in the presence of the angels of the higher heavens.

Their singing a new song symbolizes an acknowledgment and glorification of the Lord as being the only Judge, Redeemer, and Savior, thus God of heaven and earth, as may be seen in no. 279 above. Before the throne means in the Lord's presence, because He alone sits upon the throne. Before the four living creatures and before the elders means in the presence of the angels of the higher heavens (no. 369).

As it were a new song symbolizes a celebration and glorification of the Lord in the New Christian Heaven. Here specifically it means that He was acknowledged as God of heaven and earth, as He is acknowledged in the ancient heavens. This is entailed in the phrase "as it were," for "as it were a new song" means that it was seemingly new, when in fact it was not new.

We have already said before that the new heaven spoken of in Revelation 21:1 is a new heaven formed of Christians, that the prior heavens were formed of ancient peoples and most ancient ones, and that in those heavens the Lord is acknowledged as God of heaven and earth.