In bringing many sons to glory, it was fitting for God, for whom and through whom all things exist, to make the author of their salvation perfect through suffering. — Hebrews 2:10

The Captain of our salvation was made perfect through sufferings. That doesn't mean He was imperfect before — it means His work was completed through the path of pain. In Gethsemane He was sorrowful to the point of death. His sweat became like great drops of blood. The pains of death surrounded Him.