A little help, in Lighfoots commentary he gives a source as "Maim. in Retseah, cap. 2".
Where and what is this source? Does Logos sell it? Cant find anything on the web. 
Unto a lawyer, Christ defineth who is a ‘neighbour,’ by the parable of the wounded man and the good Samaritan, vastly differing from the doctrine of the Pharisees in that case. Take these two or three assertions of their own schools, for some illustration of this parable,
1. They accounted none under the term ‘brother,’ but an Israelite by blood; and none under the term ‘neighbour,’ but those that were come in to their religion. “By using the word ‘neighbour,’ are excluded all the heathen.” “An Israelite, that slayeth a stranger sojourning among them, is not to be put to death by the Sanhedrim for it; because it is said, If a man come presumptuously upon his neighbour (i)
(i) Maim. in Retseah, cap. 2.
Lightfoot, J. (1822). The Whole Works of the Rev. John Lightfoot. (J. R. Pitman, Ed.) (Vol. 3, p. 114). London: J. F. Dove.
