Red heifers were to be offered in sacrifice for the national sins, in the impressive manner described in Numbers 19:1-10, illustrating the true sacrifice for sin in the person of Christ, Hebrews 9:13,14. The well-fed heifer was a symbol of wanton wildness, Jeremiah 46:20 50:11 Hosea 4:16.
These dictionary topics are from American Tract Society Bible Dictionary published in 1859. Public Domain, copy freely.
Rand, W. W. "Entry for 'HEIFER'". "American Tract Society Bible Dictionary".