From this passage is derived the familiar symbolism of the four Evangelists; Mark seated on a lion, Luke on a steer, Matthew on a man, and John on an eagle. These are varied however. Irenaeus attributes the lion to John, and the eagle to Mark. Augustine the lion to Matthew, the man to Mark.
Lion
See on 1Pe 5:8.
Calf (μόσχῳ)
Compare Luk 15:23. In the Septuagint for an ox or steer. Exo 22:1; Eze 1:10.