Were … full translates a verb which appears only here in the Gospel of John. Its intention is to indicate the completeness of the miracle. Not only did the people eat until they were all full, but there were enough pieces left over to be gathered up and fill twelve baskets.

When they were all full may be rendered “When they had all had all they wanted to eat” or “When they had all eaten sufficiently.” It may be expressed idiomatically in some languages as “When they all said, ‘That is enough,’ ” or “When they could swallow no more” or “When their stomachs were large.”

Gather the pieces left over requires in some languages a careful choice of words. Were these pieces to be picked up from the ground after being dropped by those who were eating, or were they to be collected from the hands of those who had eaten sufficiently but still had food left over? The latter interpretation is more satisfactory, though there is no way of telling from the context precisely what happened.

Let us not waste a bit is, more literally, “that nothing may be lost” (New English Bible). Although the word “lost” is sometimes used to refer to the condition of persons estranged from God, in the present context the meaning is obviously that of being wasted (Moffatt “so that nothing may be wasted”; see also Jerusalem Bible and New American Bible). Good News Translation takes it with this meaning, and changes the passive structure into an active one with a direct object.

Let us not waste a bit may be rendered “we should not waste any of the food.” The term waste may be rendered in some languages “cause to be ruined,” but there are certain advantages in having it rendered “not to be used,” for example, “we should not cause this food not to be used” or, expressed positively, “we should cause all the food to be used.”

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on the Gospel of John. (UBS Handbook Series). New York: UBS, 1980. For this and other handbooks for translators see here .