Why do Catholics do that?

Why do Catholics honor the image of the Sacred Heart of Jesus?

The image of the Sacred Heart of Jesus is a symbol of Christ’s love for us. It is often a heart surrounded by flame, pierced by a lance, topped by a cross, and circled by a crown of thorns. Jesus’ love for us burns bright and intense like a flame. His heart is pierced by the lance representing our sins and the crown of thorns and the cross remind us of the death he suffered to bring us life.