Perfection of parts and perfection of degrees
Thesis XXII. Close to this distinction is another, which commonly divides perfection into perfection of parts and perfection of degrees. Obedience perfect in degree reaches the highest degree of perfection: through it a person conforms and submits himself to the law so perfectly that nothing at all can be found lacking in him and he can make no further improvement in that respect. In this sense, as we maintain and as is self-evident, no one fulfils the law perfectly in this life.
Obedience that falls well short of the highest degree can still be, and be called, perfect in its parts. As to its parts, essential or integral, it lacks none of what is needed for true obedience acceptable to God. In this sense the obedience of the godly in this life is perfect, and in this respect believers renewed by Christ's grace and led by his Spirit can fulfil God's law perfectly: that is, they can give his commandments a true, sincere obedience that pleases God. The essential perfection of such a thing is simply its being true and sincere.
Latin
XXII. Huic distinctioni affinis est altera, juxta quam distingui solet perfectio in perfectionem partium & perfectionem graduum. Perfecta secundum gradus obedientia illa est quae attingit summum perfectionis gradum, & per quam aliquis legi ita perfecte se conformat & subjicit, ut in eo nihil prorsus desiderari queat, neque hoc respectu possit in melius proficere. Hac ratione contendimus, & per se manifestum est legem a nullo perfecte in hac vita impleri. Verum obedientia quae multum a summo gradu perfectionis abest, nihilominus esse & dici potest perfecta secundum partes; quoniam respectu partium, sive essentialium, sive integrantium, nihil illi deest eorum quae necessaria sunt ut sit obedientia vera & Deo accepta. Hoc sensu perfecta est obedientia piorum in hac vita, & hoc respectu fideles qui sunt per Christi gratiam renovati, & spiritu illius ducuntur, perfecte Dei legem implere possunt, id est, verum & sincerum, Deoque gratum obsequium mandatis illius praebere. Nec enim essentialis ejusmodi perfectio aliud est quam ipsius rei veritas atque sinceritas.