64 Pa. Stat. § 442
In all cases where the whole amount of any mortgage or lien which shall have been executed or have taken effect before the passage of this act, and has become due and payable to the commonwealth before the passing of this act, or shall become so due and payable, or any part thereof, before the said first day of May, 1827, or at any time thereafter, if the mortgagor or judgment debtor shall on or before such time fully pay the interest which may have accrued on any such mortgage or lien, at the time of such payment, suit for the recovery of the principal shall not be instituted for one year thereafter; but in default of such payment, the secretary of the land office shall proceed from and after said time to cause suits to be instituted for the recovery of the same, under and agreeably to the provisions of the above recited act of March 22, 1820: Provided, That if any mortgagor or judgment debtor having so paid up the interest due on such mortgage or lien shall well and truly pay the interest which may have accrued on such mortgage or lien on or before the first day of June in each and every year thereafter, suits shall not be brought as aforesaid for the recovery of the amount of such mortgage or lien, and the interest which may be due thereon, for one year after failure to pay the interest on the same, unless it shall be otherwise directed by law.
64 P.S. § 442