'Sign' in the Bible

And thou shalt bind them for a sign upon thy hand, and they shall be for frontlets between thine eyes.

Therefore shall ye lay up these my words in your heart and in your soul; and ye shall bind them for a sign upon your hand, and they shall be for frontlets between your eyes.

If there arise in the midst of thee a prophet, or a dreamer of dreams, and he give thee a sign or a wonder,

and the sign or the wonder come to pass, whereof he spake unto thee, saying, Let us go after other gods, which thou hast not known, and let us serve them;

and they shall be upon thee for a sign and for a wonder, and upon thy seed for ever.