My mom became a mom on February 12, 1971. She later became a mother for the second time on June 10, 1973 with the arrival of my sister. But it would be silly for my mom to say, "I was a mother on Feb. 12 and June 10". The verb "was" does not make sense here. Motherhood is not just something that happens at a particular point in time when a little one makes their appearance in this world. Motherhood is rather a current condition/title that implies duties and privilages that never end. If we want to correctly talk about motherhood we need to practice correct verb usage. Past tense verbs don’t work (My high school English teacher would be so proud). Instead mothers say, "I am a mother".
The same goes with baptism. Too often we say, "I was baptised on (such and such a date)". The past tense verb is used as if baptism is an event in the past; something over and done with. But like motherhood, using the past tense verb with baptism does not work. Your baptism is not something that happened in the past and now is done, but your baptism is something you live everyday of your life. Baptism is something your are and not something you were. Baptism is a gift and something that is received in faith. When that happens, why would anyone possibly want to put that gift in the closest. Rather we are called to live as baptized children of God to the glory of God. So the correct verb usage is: "I am baptized" You say that phrase with confidence because it means you have been claimed and chosen by God ("You did not choose me, but I choose you" John 15:16) Live as if you are baptized and chosen by God so others may see God’s glory and the promise of New Life through Jesus Christ. Amen!