Why was burnt offerings performed in the bible?

Christian View

Animal sacrifices were required until their seed would come (Jesus Christ), he was the only perfect man to make up for what Adam lost. Romans 5:12, 15 But Until that time would come Jews had to make sacrifices for their sins and to prepare them for the Messiah, Jesus Christ.

Galatians 3:19-25 Explains: 19Why, then, the Law? It was added to make transgressions manifest, until the seed should arrive to whom the promise had been made; and it was transmitted through angels by the hand of a mediator. 20Now there is no mediator where only one person is concerned, but God is only one. 21Is the Law, therefore, against the promises of God? May that never happen! For if a law had been given that was able to give life, righteousness would actually have been by means of law. 22But the Scripture delivered up all things together to the custody of sin, that the promise resulting from faith toward Jesus Christ might be given to those exercising faith. 23However, before the faith arrived, we were being guarded under law, being delivered up together into custody, looking to the faith that was destined to be revealed. 24Consequently the Law has become our tutor leading to Christ, that we might be declared righteous due to faith. 25But now that the faith has arrived, we are no longer under a tutor.

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Jewish view

One of the topics in the Torah (Leviticus ch.1-8) is that of sacrifices. Since the Holy Temple doesn't exist today, we don't now offer sacrifices. In earlier times, sacrifices were one of the ways of serving God; a type of physical prayer. They consisted of bullocks, goats, sheep, rams, turtle-doves, or fine flour, accompanied by an offering of oil and of wine (see Numbers ch.15).