It is more than stronly recommended. It is commanded by Jesus personally, and also by His Apostles.
"It {Baptism by immersion}is more than strongly recommended. It is commanded by Jesus personally, and also by His Apostles."
Jesus also commands us to eat His body and drink His blood, or "you shall not have eternal life within you". Not to open another subject, (Eucharist) but why do you follow one teaching to the letter with no room for any other interpretation, and not the other?
Regards