Sabbath Permissions

In illo tempore abiit Jesus per sata sabbato: discipuli autem ejus esurientes coeperunt vellere spicas, et manducare. Pharisaei autem videntes dixerunt ei: Ecce discipuli tui faciunt, quod non licet eis facere Sabbatis.. Ecce reprehensiva interrogatio: et dicit tria; superstitionem, suspicionem, et interrogationem, Superstitio notatur in nomine Pharisaeorum: quia gloriabatur de religione superstitiosa, unde infra, assiimilantur sepulchris, quae a foris apparent speciosa, et intus, sunt plena spurcitiis. Videntes' suspicionis oculo. An oculus tuus nequam est: quia ego bonus sum. Quid autem vides festucam in oculo fratris tui: et trabem in oculo tuo non confideras? Et patet hoc: quia isti non sequebantur Christum, nisi ut invenirent accusationem contra eum. Dixerunt ei. Contra dicitur: Quod dixerunt discipulis; non Christo. Ad hoc dicendum, quod primo dixerunt discipulis: et cum desistere nollent, dixerunt Christo: et sic utrumque factum est. Sed iste narrat hic quod directe facit ad solutionis legis occasionem. Ecce discipuli tui. Reprehensiva est interrogatio: ut aut prohiberet, aut legem accusaretur soluere, quasi dicant: Malus magister in discipulorum illegali ostenditur conversatione. Qualis rector civitatis, talis et qui habitant in ea. Est autem istud derogatio et detractio discipulorum, et apparens Christi reprehensio. Detractores Deo odibiles. Adetractione parcite linguae: quia sermo obscurus in vacuum non ibit. Faciunt quod non licet facere Sabbatis. Non enim accusare poterant factum: quia dicitur, Si intraveris segetem amici tui, granges spicas, et manu conteres; sed falce non metes. Constricationem autem volebant esse praeparationem: quia cibos non licebat praeparare die Sabbati, quamvis liceret panem incidere et mensam ponere et amovere, et huiusmodi. Et videtur Dominus supponere verum esse dictum eorum: quia respondet, acti discipuli voluant Sabbatum; eo quod licet discipuli in facto per necessitatem famis sint excusati; tamen quia intendit soluere, potius respondet ad intentionem Pharisaeorum, quam se convertat ad facti excusationem. Facit tamen utrumque in litera, sicut patebit, licet finaliter non intendat nisi solutionis ostensionem. Et sic hic quod dicit Reprobatio quidem fit praecedentis mandati propter infirmitatem eius et inutilitatem: nihil enim ad perfectum adduxit lex: introductio vero fit melioris speci, per quam proximamus Deum. Sanctus Albertus Magnus Commentarium In Evangelium Mattheum, Caput XII Source: Here p108

At that time Jesus went through the corn on the Sabbath and His disciples who were hungry began to pluck the ears and eat. Seeing this the Pharisees said to Him, 'Behold, your disciples do what is not permitted on the Sabbath.' 1 Oberve the interrogation of censure, and it declares three things, supersition, suspicion and questioning. Superstition is noted in the name of the Pharisees, because theirs was to glory in a superstitious religion, whence below it is said, 'They are like tombs which are fair without and within they are full of foulness.' 2 'Seeing...' the suspicion of the eye. 'Is your eye wicked because I am good?' 'For you see the speck in your brother's eye and you do not grasp the plank in your own.' 3 And it reveals this, that they did not follow Christ, unless to find some accusation against him. 'They said to Him...' Now against this it is said in Luke that they spoke to His disciples and not to Christ. To this it must be said that first they spoke to the disciples and when they were unwilling to desist, they spoke to Christ, and so both things were done. But here he tells what He did to settle this matter of the Law. 'Behold your disciples...' An interrogation of censure, that He should either prohibet it or be accused of flouting the Law, as if they had said. 'A wicked teacher is shown by the conduct of his pupils.' 'As the governor of a city, so those who dwell there.' This is the derogation and detraction of the disciples, and the open reprehension of Christ. 'Detractors are hateful to God' 'From detraction withhold your tongue, because a word does not go out into nothingness.' 4 'They do what is not permitted on the Sabbath...' They were not able to accuse the act, because it is said: 'If you enter into the crop field of your friend, you may break off the ears and crush them in your hands, but your may not reap with the sickle.' 5 But they would have the crushing as preparation, since it is not permitted to prepare bread on the Sabbath, although it is permitted to take to bread and set the table and clear it, and similar things. And it seems the Lord supported the truth of what they said, because He answered that the acts of the disciples did flout the Sabbath, yet it was permitted to the disciples because of the necessity of the hunger they suffered. However because He intended to set it aside He rather addressed the intent of the Pharisees than turn to excuse for the deed. However He did both in the text, as it was to be revealed, and it is possible He did not intend anything but a revelation of abolishment. And so it is said: 'The reproof of a former command is set aside because of its weakness and uselessness, for the Law made nothing perfect, but a better hope is introduced, by which we may draw closer to God.' 6 Saint Albert The Great, Commentary On The Gospel of St Matthew, Chapter 12 1 Mt 12.1-2 2 Mt 12.23 3 Mt 20.15 , Mt 7.3 4 Eccl 10.2, Rom 1.30 Wisd 1.11 5 Deut 23.25 6 Heb 7.18-19