Jesus called out with a loud voice, “Father, into your hands I commit my spirit.” When he had said this, he breathed his last. –Luke 23:46
From John Stott:
Between them the evangelists use four different expressions, each of which places the initiative in the process of dying in Jesus’s own hands. Mark says he “breathed his last” (Mark 15:37), and Matthew that he “gave up his spirit” (Matt. 27:50), while Luke records his words, “Father, into your hands I commit my spirit” (Luke 23:46). But John’s expression is the most striking, namely that “he bowed his head and gave up his spirit” (John 19:30). The verb is again paradidomi, which was used of Barabbas, the priests, Pilate, and the soldiers who “handed over” Jesus. But now John uses it of Jesus himself, handing over his spirit to the Father and his body to death. Notice that before he did this he “bowed his head.” It is not that he first died, and then his head fell forward onto his chest. It was the other way around. The bowing of the head was his final act of surrender to the will of his Father. So by word and deed (bowing the head and declaring that he was handing over his spirit), Jesus indicated that his death was his own voluntary act.
Jesus could have escaped death right up to the last minute. As he said in the garden, he could have summoned more than twelve legions of angels to rescue him. He could have come down from the cross, as his mockers challenged him to do. But he did not. Of his own free will and deliberate choice he gave himself up to death. It was he who determined the time, the place, and the manner of his departure.
The last two words from the cross (“finished” and “I commit my spirit”) proclaim Jesus as the conqueror of sin and death. We must come humbly to the cross, deserving nothing but judgment, pleading nothing but mercy, and Christ will deliver us from both the guilt of sin and the fear of death.
-from Through the Bible ~ Through the Year by John Stott
Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death he might destroy the one who has the power of death, that is, the devil, and deliver all those who through fear of death were subject to lifelong slavery. –Hebrews 2:14