Lest

LEST, conjunction That not; for fear that.

Ye shall not eat of it, neither shall ye touch it, lest ye die. [[Genesis 3#3|Genesis 3:3]].

The phrase may be thus explained. Ye shall not touch it; that separated or dismissed, ye die. That here refers to the preceding command or sentence; that being removed or not observed, the fact being not so, ye will die.

Sin no more, lest a worse thing come to thee. [[John 5#14|John 5:14]].

Sin no more; that fact not taking place, a worse thing will happen to thee.