Said trustees shall also have power and authority to bargain, sell, convey, mortgage, lease or release any real estate belonging to said church or held by them as such trustees, and to erect churches, parsonages, school houses and other buildings for the direct and legitimate use of such church and to alter and repair the same, and to fix the salaries of their ministers: Provided, That no such purchase, sale or conveyance, mortgage, lease or fixing of salaries shall be made unless the vote of at least a majority of the members of the church organizations of which said trustees are officers, shall be first obtained at a meeting of such members of said church or congregation present and entitled to vote at any meeting of the members of such church or congregation duly and especially called for that purpose, by notice given for 2 successive Sabbaths at the usual place of meeting next preceding such meeting: Provided further, That no sale, mortgaging or conveyance shall be made of any gift, grant or donation, conveyance, devise or bequest which would be inconsistent with the express terms or plain intent of the grant, donation, gift, conveyance, devise or bequest.