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Study Dictionary
Simplicity
SIMPLICITY [ISBE]
SIMPLICITY - sim-plis'-i-ti (pethayyuth; haplotes): The words in the Old Testament commonly translated "simplicity" are pethi, "simple" (Prov 1:22), pethayyuth, "simplicity" (9:13 margin), tom, "completeness," "integrity" (2 Sam 15:11), "They went in their simplicity." In the New Testament, haplotes, "singleness of mind," "simplicity," occurs in Rom 12:8, "He that giveth let him do it with simplicity," the Revised Version (British and American) "liberality," margin "Greek: `singleness'"; 2 Cor 1:12, "in simplicit and godly sincerity," the Revised Version (British and American) (with corrected text) "in holiness and sincerity of God"; 2 Cor 11:3, "the simplicity that is in Christ," the Revised Version (British and American) (with corrected text) "the simplicity and the purity that is toward Christ"; compare Eph 6:5; Col 3:22, where the translation is "singleness" In The Wisdom of Solomon 1:1 we have, "Think ye of the Lord with a good mind (the King James Version "heart"), and in singleness (the King James Version "simplicity") of heart seek ye him" (haplotes). our Lord also speaks (Mt 6:22; Lk 11:34) of the "single eye" (haplous), and James (1:5) applies haplos, "simply," "directly," without after-thought (the King James Version and the Revised Version (British and American) "liberally") to God, who had been described by Plato (Rep. ii.382 E) as being perfectly simple (haplous) and true, both in word and deed. In such "simplicity"--openness, sincerity, freedom from double-mindedness--man most resembles God and is most open to His visitation and blessing.W. L. Walker
Also see definition of "Simplicity" in Word Study