What does Mark 8:5 mean?

"Loaves" is another variant on the Greek word for bread. It may refer to flat bread, about the size of a dinner plate. Some draw a parallel between this moment and Jesus' breaking of bread at the Last Supper, but the intent and meaning are very different. Also, this probably wouldn't have been the same as the bread that Jesus tore off and dipped at the last supper (Mark 14:20), since the Jews only ate unleavened bread during the Passover feast.

Seven such loaves are obviously too small a meal for four thousand men plus women and children (Matthew 15:38), even adding a few small fish (Mark 8:7). In Jesus' hands, however, it is enough for everyone to have their fill (Mark 8:8)—for the moment. Jesus knows that His feeding miracles are a double-edged sword. The people are filled with bread now, but will be back when they get hungry again (John 6:26). Although they want bread, what they need more is the "the food that endures to eternal life" (John 6:27). Our physical needs are important, but they are not something to be anxious about (Matthew 6:31). Like the woman at the well needed living water, we need the bread of life—Jesus—who will fill our spiritual hunger for eternity (John 6:35).

Once we have Jesus, the worry for our earthly needs will diminish as our concern for God's kingdom increases. God promises that He knows what we need, and He will "add" to our supply, but He doesn't promise that we will never go hungry (Matthew 6:32–33). His goal is that we will grow to value Him even more than our own lives.