It seems there were sprinklings and immersions in the ritual cleansing of the old covenant, from what I have read. I am not entirely sure that mode is all important or that everyone in the New Testament would have used the same mode (I have heard and read that the earliest pictures we have are of people standing in water and water being 'affused' on the head; but that the didache prescribed immersions, and that probably people would have practiced a mode baptism similar to a ritual cleansing with which they were familiar? one such article here).

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Heidi
Indianapolis, Indiana

After two days, he will revive us; on the third day he will raise us up, that we may live before him.
Let us know; let us press on to know the LORD; his going out is sure as the dawn; he will come to us as the showers, as the spring rains that water the earth.