'Sincerity' in the Bible

And, now, if in truth and in sincerity ye have acted, when ye make Abimelech king; and if ye have done good with Jerubbaal, and with his house; and if according to the deed of his hands ye have done to him --

yea, if in truth and in sincerity ye have acted with Jerubbaal and with his house this day, rejoice ye in Abimelech, and he doth rejoice -- even he -- in you;