No policy of life or endowment insurance shall be issued or delivered in this state (1) if it contains in substance a provision by which the policy shall purport to be issued, or to take effect, more than six months before the original application for the insurance was made, (2) if it contains in substance a provision which excludes or restricts liability in the event of death by suicide if such death occurs more than two years after the policy date, (3) if it contains in substance provision, except such provisions as are authorized or required by section 44-502, by which the settlement at the maturity of any policy after the expiration of the contestable period thereof shall be of less value than the amount promised on the face of the policy plus dividend additions, if any, less any indebtedness to the company on or secured by the policy, and less any premium that may, by the terms of the policy, be deducted, or (4) if there are attached thereto or issued as a part thereof or in connection therewith any coupons or other evidence of indebtedness by whatever name called, which coupons or other evidence of indebtedness are to be used in reducing the premiums on the policies or for the purchase of additional insurance or any benefit whatever or which are to be redeemed by the company in cash under any circumstances in the nature of a rebate on the premium.