Mark 8:1-9 narrates the feeding of 4000 that Jesus is now referencing — the seven baskets come from that event.

Mark 8:8 is the direct record of the seven baskets Jesus asks about — the result of the 4000 feeding.

Mark 6:43 records twelve baskets from the 5000, providing the counterpart number Jesus contrasts with the seven here.

Matthew 15:34-38 gives Matthew's parallel account of the feeding of 4000, confirming the seven baskets.

2 Kings 4:43 records Elisha's feeding of a hundred men — an OT type of Jesus' greater feeding miracle.

Luke 9:17 records the twelve baskets from the 5000, serving as the contrasting number to the seven in Jesus' question.