Perpetuity of existence. The doctrine of immortality is taught in the Old Testament. It is plainly implied in the writings of Moses (Genesis 5:22,24; 25:8; 37:35; 47:9; 49:29, Compare Hebrews 11:13-16; Exodus 3:6, Compare Matthew 22:23). It is more clearly and fully taught in the later books (Isaiah 14:9; Psalms 17:15; 49:15; 73:24). It was thus a doctrine obviously well known to the Jews.
With the full revelation of the gospel this doctrine was "brought to light" (2 Timothy 1:10; 1 Corinthians 15; 2co 5:1-6; 1 Thessalonians 4:13-18).
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain, copy freely.
Easton, Matthew George. "Entry for 'Immortality'". "Easton's Bible Dictionary".