Hebrews 9 is not about any ordinary will. It speaks about the New Covenant, and shows it to be the will of Jesus Christ (Hebrews 9:15-16). The execution of Jesus Christ on the cross is the death that caused His will to be carried out (Hebrews 9:12, 14, 15, 26, 28). Was the will or covenant of Christ in effect during His earthly life? No, for Hebrews states,
For where a will is involved, the death of the one who made it must be established. For a will takes effect only at death, since it is not in force as long as the one who made it is alive. (Hebrews 9:16-17)
Clearly, Christ’s New Covenant was not in effect during His earthly life. It went into effect after His death. That is the nature of a last will and testament; it requires the testator’s death to set it in motion.
Christ’s death activated His will.
A death is essential for a will to take effect, and that relates to the importance of blood. The next verses of Hebrews 9 point out that even the First Covenant used blood for its beginning.
Therefore not even the first covenant was inaugurated without blood. For when every commandment of the law had been declared by Moses to all the people, he took the blood of calves and goats, with water and scarlet wool and hyssop, and sprinkled both the book itself and all the people, saying, “This is the blood of the covenant that God commanded for you.” (Hebrews 9:18-20; verse 20 quotes from Exodus 24:8)
According to Hebrews 9 and Exodus 24, Moses placed “the blood of the covenant” on the people, the Book of the Law (the scroll), and the things of worship. But that old place of worship was just a “symbol” or “illustration” (Hebrews 9:9). Its sacred things were just “copies” (Hebrews 9:23-24). Animal blood was merely a shadowy hint of the blood that would truly save—the blood of Jesus.