1. What must be done with sin before baptism can occur?
The sin has to be stopped, terminated. We need to act no more in our sins.
What events from Christ's life are symbolized in baptism?
The burial of Christ is symbolized in baptism, as we are submerged, as if being buried underground and coming back, a renewed Spirit. So that is the Resurrection of Christ, lifted from death.
Considering this symbolism, why couldn't someone be baptized by sprinkling?
We wouldn't have the deeper meaning and symbolism of baptism of we were simply sprinkled. Christ was even baptized, as an example to us. Without complete immersion, you don't have the "death" or the "rebirth/resurrection".
What do these verses teach us about how we can maintain the "newness of life"?
It teaches us that if we continue to model our lives after Christ, and follow in his footsteps, we won't feed our sinful side. If we remember that if we are sinning then it is like having half baptism, we don't get to enjoy the greatness of emerging from the death and rising.
According to Mosiah 3:19, what part of us would ideally die at baptism?
Our Natural Man should die as we come unto Christ and try to make correct choices. We become more humble, and get rid of our selfishness/natural man who is enemy to God.
2. Romans 6:13-23 How do we know who's servant we are? What is the true source of freedom?
Our Heavenly Father and Jesus Christ gave us a way to be rid of our sins and to lead a life of righteousness. We can choose whose servants we will be. If we serve our Natural Man, we will be servants of the devil, but if we focus and serve our Lord, then we can stand as witnesses of him.
The true source of freedom is righteousness. Through Christ, all are made free. Sin binds us down in misery.