The verb “to plenish”, no longer in use today, is derived from the Latin plenus: “full, filled, greatly crowded; stout, pregnant; abundant, abounding; complete”, from which words like “plenty”, “plentiful”, “plenitude”, and “replenish” are derived.
Any assembly with full attendance, such as the UN General Assembly, is called a plenum. A plenary school assembly denotes full attendance of all students and faculty.
Christ was brought to earth by a remnant of followers of God who were so fully present with God that God was with them — along with all the hosts of heaven in plenary attendance. In one accord with Allness, this remnant was able to replenish a Christ-depleted earth drowning in materialism; by a new and living Way, they ushered in the Christ, and so began the Christian era.
In Genesis 1:28, replenishment is not simply filling up depleted space and stopping there, but is an energetic, ever-happening endeavor, bestowing blessings upon earth that are constantly begetting more, each one increasing in blessedness (think of Mrs. Eddy publishing the CS Monitor with greater energy than that of a girl seventy earth-years younger than she). In other words, replenishing the earth is God’s omni-activity operating through lives dedicated to Him in full, uninterrupted surrender.
Replenishment is what Jesus meant by “life, and life more abundantly,” and which he demonstrated by healing great multitudes of people in an afternoon, the multiplication of the loaves and fishes, etc. This is also how God blessed His creation on the seventh day, not calling it merely “good,” as on previous days, but “very good,” heavenly good that is bristling with activity, constantly replenishing those that are replenishing the earth with it.
Replenishing the earth is my assignment. “God rests in action.” (SH 519:25.) Therefore, God grant that I may enter into His rest, to manifest the light of His Day every moment of my life, and,
like a wise virgin, replenish a light-famished world by seeing it filled to overflowing with the radiance of the Christ.
Seeing the world right-side up turns its evils upside-down, so that every space, every corner that darkness once claimed as exclusively its own is refreshed, restored, renewed — replenished — with the light of “eternal noon, unmarked by a setting sun.” (SH, first edition, p. 212.)