Rev 4:8

8 and the four living creatures, having each one of them six wings, are full of eyes around about and within. They have no rest day and night, saying, Holy, holy, holy is the Lord God, the Almighty, who was and who is and who is to come. 

Holy, holy, holy – some early texts, and the Majority text lists nine holys, for the Almighty God. This is compared to the three holys in Isaiah 6:3, applied to the Spirit of Christ, as the YHVH (He WILL BE) of Hosts .

Holy, holy, holy (WHO WAS)
Holy, holy, holy (WHO IS)
Holy, holy, holy (WHO IS TO COME)