9. tree of life--so called from its symbolic character as a sign
and seal of immortal life. Its prominent position where it must have
been an object of daily observation and interest, was admirably fitted
to keep man habitually in mind of God and futurity.
tree of the knowledge of good and evil--so called because it was
a test of obedience by which our first parents were to be tried,
whether they would be good or bad, obey God or break His commands.
JFB.
Picture Study Bible