Goods and chattels pledged, assigned or mortgaged as security for any debt or contract, may be levied upon and sold on execution against the person making the pledge, assignment or mortgage subject thereto; and the purchaser shall be entitled to the possession when it is held by the pledgee, assignee or mortgagee, on complying with the conditions of the pledge, assignment or mortgage.
Tex. R. Civ. P. 643