Why do Christians get baptized?

Baptism is the symbolic action of recognizing that of Jesus died for your sins, was buried in a tomb, and rose from the dead. And that when you are baptized, you are being raised to a new life, cleansed from the sin of the past.

Jesus Christ commanded that believers [later called Christians] be baptized:

Mar 16:15 And He said to them, Go into all the world, proclaim the gospel to all the creation.

Mar 16:16 He who believes and is baptized will be saved, but he who does not believe will be condemned.

Mat 28:18-20 MKJV And Jesus came and spoke to them, saying, All authority is given to Me in Heaven and in earth. (v.19) Therefore go and teach all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, (v.20) teaching them to observe all things, whatever I commanded you. And, behold, I am with you all the days until the end of the world. Amen.

Rom 6:3 Or do you not know that as many as were baptized into Christ Jesus were baptized into his death?

Rom 6:4 Therefore we have been buried with him through baptism into death, in order that just as Christ was raised from the dead through the glory of the Father, so we too may live a new life.

Rom 6:5 For if we have become united with him in the likeness of his death, we will certainly also be united in the likeness of his resurrection.

Rom 6:6 We know that our old man was crucified with him so that the body of sin would no longer dominate us, so that we would no longer be enslaved to sin.

Rom 6:7 (For someone who has died has been freed from sin.)

Rom 6:8 Now if we died with Christ, we believe that we will also live with him.

Col 2:12 Having been buried with him in baptism, you also have been raised with him through your faith in the power of God who raised him from the dead.

Col 2:13 And even though you were dead in your transgressions and in the uncircumcision of your flesh, he nevertheless made you alive with him, having forgiven all your transgressions.

1Pe 3:18 [GNB] For Christ died for sins once and for all, a good man on behalf of sinners, in order to lead you to God. He was put to death physically, but made alive spiritually,

1Pe 3:19 and in his spiritual existence he went and preached to the imprisoned spirits.

1Pe 3:20 These were the spirits of those who had not obeyed God when he waited patiently during the days that Noah was building his boat. The few people in the boat---eight in all---were saved by the water,

1Pe 3:21 which was a symbol pointing to baptism, which now saves you. It is not the washing off of bodily dirt, but the promise made to God from a good conscience. It saves you through the resurrection of Jesus Christ,

1Pe 3:22 who has gone to heaven and is at the right side of God, ruling over all angels and heavenly authorities and powers

Another answer:There are 2 types of baptism: baptism of water (where the person get dunked in water or water sprinkled on their head) and Spiritual baptism (which is when the Holy Spirit enters the body).

Baptism is a way of cleansing the person of their former sin, and returning them to the pure state that means God can live within them (and satan cant live in them). This person is then able to begin their personal relationship with God.

As the Holy Spirit (and therefore God) enters the Christian, the person is connected with Jesus (who died for our sins) who showed us that we will live again (when He was resurrected) and therefore promises us eternal life.

When a person is baptised with water, it is just a symbol of spiritual baptism, which can happen at any time without a ceremony.

Baptism also affiliates (joins) a person to a particular church.