Charles Ellicott Commentary Matthew 12:4

"how he entered into the house of God, and ate the showbread, which it was not lawful for him to eat, neither for them that were with him, but only for the priests?" — Matthew 12:4 (ASV)

How he entered into the house of God — Strictly speaking, this was in the tabernacle at Nob, where Ahimelech (possibly assisted by Abiathar, Mark 2:26) was ministering as high priest (1 Samuel 21:6). The showbread, or “bread of offering,” consisted of twelve loaves in two rows of six each. These were presented every Sabbath day (Exodus 25:30; Exodus 40:23; Leviticus 24:5–9), and the loaves from the previous week were then removed and reserved for the exclusive use of the priests.

In this case, however, the necessity of the situation was allowed to override the ceremonial ordinance. Our Lord teaches through this single instance the general principle that when positive commands and necessities involving human well-being come into conflict, the latter must prevail over the former.