'Sincerely' in the Bible

Now therefore, if ye have done truly and sincerely, in that ye have made Abimelech king, and if ye have dealt well with Jerubbaal and his house, and have done unto him according to the deserving of his hands;

If ye then have dealt truly and sincerely with Jerubbaal and with his house this day, then rejoice ye in Abimelech, and let him also rejoice in you: