There are some who say Baptism should only be given to adults because we must first have repentance and faith. Earlier I was asked to comment on this subject and recently found the teaching of Elder Cleopa on this topic.The Elder begins his explanation by pointing out the precursors to Baptism found in the Old Testament. He writes,There in [the Old Testament] we read how God appeared to Abraham when he was ninety-nine years of age and, among things, told him to circumcise all the men and to circumcise all the male children who would be born from that time on on the eighth day after their birth. As for him who would not be circumcised , he would perish (Gen 17: 10-14). We see, then, that God did not say to Abraham that children and youth should be circumscribed when they became adults... Some say the Baptism of babies is meaningless since they don't understand anything when they are Baptized. But what did Issac, Abraham's child, understand on the eighth day? Undoubtedly he understood nothing. His parents, however, understood. This is how it is with Baptism as well, as it is practiced in the Orthodox Church, since it is well-known that circumcision symbolizes Baptism in the Old Testament.He gives another example of the Exodus from Egypt and the passage through the Red Sea

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