Strictly speaking, from that clip Bieber can only be said to be non-Homoiousian, but not necessarily Arian.
Is that true though? I fail to see how referring to both Jesus (i.e. God the Son) and God (i.e. God the Father) implies they are not of identical substance. All orthodox trinitarian conceptions of God do make a distinction between Jesus and the Father as separate persons, and throughout the bible there are numerous references within the same verse to both God and the Lord Jesus Christ (cf 1 Cor. 8:6 "there is but one God... and one Lord Jesus")
Arianism is more than simply holding that the father and son are not the same personae, tho that along with not having the same substance is a consequence of the central tenet of Arianism, that the Son was created by the Father. I'll grant that it's logically consistent for there to be multiple personae with the same substance. However, the way he expressed himself indicates to me a rejection of the concept that God the Father and Jesus have a common substance.
