He was speaking on Monday as he addressed the Senate floor for the first time and called for the reintroduction of the death penalty to reduce crime related to illegal drugs.
He said the death penalty was appropriate for the "most heinous" of crimes that destroy families and ruin lives.
Mr Pacquaio went on: "The death penalty is lawful, moral and sanctioned governmental action.
"Having read the Bible on a regular basis, I am convinced that God is not just a God of mercy, but also a God of justice."
During the speech, he also used quotes from Bible passages and gave example of incidents where justice is served.
When asked how those being punished should die the Christian boxer said firing squad or hanging would be most preferable, according to Inquirer.net.
