The Mitzva of Pidyon Haben was mentioned in Parshat Korach. The “redemption of the first born,” is still applicable today. A first born baby boy after thirty days, must be redeemed by a Kohein.
The rationale for this Mitzva is that the first born must acknowledge that they were saved in Egypt. The tenth plague that took the lives of every first born Egyptian, did not apply to Jewish babies. It must never be forgotten how Hashem “passed over” the Jewish homes and saved the Jewish first born.
The ceremony today, involves the father of the baby, presenting him to a Kohein. He is asked by the Kohein whether he prefers to redeem his first born son, or have him sanctified to G-d. The father answers that he wishes to redeem him, with the presentation of five silver coins. The Kohein waves the coins over the baby, and announces that the coins succeeded in redeeming the baby.
This ceremony does not apply if the baby is the son of either a Kohein or Levi, on either side of the family. The exception to this rule would be where the mother, a daughter of a Kohein, becomes pregnant by a non-Jew. Her first born baby requires a Pidyon Haben, because she has been disqualified as a Bat Kohein, with her union with a non-Jew.
Similarly, a regular Jewish woman becomes pregnant by a non-Jew, her first born needs a Pidyon Haben.
The obligation of Pidyon Haben falls on the father of the baby. Therefore, if one’s father is not available, the child needs to redeem himself.
There must be numerous first born Jews out there, who have never had a Pidyon Haben. It is never too late. This ceremony can even be done on an adult first born. If you are a first born male, or if you know one, they should be urged to perform this important Mitzva of Pidyon Haben.