"With a holy sadness Jesus comforted and cheered the angels and informed them that hereafter those whom He should redeem would be with Him, and that by His death He should ransom many and destroy him who had the power of death. And His Father would give Him the kingdom and the greatness of the kingdom under the whole heaven, and He would possess it forever and ever. Satan and sinners would be destroyed, nevermore to disturb heaven or the purified new earth. Jesus bade the heavenly host be reconciled to the plan that His Father had accepted and rejoice that through His death fallen man could again be exalted to obtain favor with God and enjoy heaven. EW 151.1"
"And every creature which is in heaven, and on the earth, and under the earth, and such as are in the sea, and all that are in them, heard I saying, Blessing, and honour, and glory, and power, be unto him that sitteth upon the throne, and unto the Lamb for ever and ever."
Both passages describe a scene of praise and reconciliation in heaven, centered around the Lamb (Jesus) and His sacrifice. The EGW passage elaborates on the reasons for this praise, while Revelation 5:13 provides a general picture of universal adoration.
"Then joy, inexpressible joy, filled heaven. And the heavenly host sang a song of praise and adoration. They touched their harps and sang a note higher than they had done before, for the great mercy and condescension of God in yielding up His dearly Beloved to die for a race of rebels. Praise and adoration were poured forth for the self-denial and sacrifice of Jesus; that He would consent to leave the bosom of His Father, and choose a life of suffering and anguish, and die an ignominious death to give life to others. EW 151.2"
"Saying with a loud voice, Worthy is the Lamb that was slain to receive power, and riches, and wisdom, and strength, and honour, and glory, and blessing."
Both passages describe a scene of joy and praise in heaven, specifically focused on the sacrifice of Jesus (the Lamb) and His worthiness. The EGW passage provides more detail about the reasons for the joy, while Revelation 5:12 gives a specific declaration of worthiness.
"Said the angel, “Think ye that the Father yielded up His dearly beloved Son without a struggle? No, no. It was even a struggle with the God of heaven, whether to let guilty man perish, or to give His beloved Son to die for him.” Angels were so interested for man's salvation that there could be found among them those who would yield their glory and give their life for perishing man, “But,” said my accompanying angel, “that would avail nothing. The transgression was so great that an angel's life would not pay the debt. Nothing but the death and intercessions of His son would pay the debt and save lost man from hopeless sorrow and misery.” EW 151.3"
"For it is not possible that the blood of bulls and of goats should take away sins."
Both passages emphasize that only a specific sacrifice (Jesus' death in EGW, not animal sacrifices in Hebrews) can atone for sin. The EGW passage expands on why an angel's sacrifice would be insufficient, while Hebrews 10:4 focuses on the inadequacy of animal sacrifices.