The question may be asked, whether this command is to be taken metaphorically or literally. No doubt the remembrance of the great deliverance was intrusted to acts. Besides the annual Passover feasts, inscriptions on the door-posts and fringes on the dress were appointed for this purpose. And the Jews from a very early period, certainly before our Lord's time, wore phylacteries fastened, as this and other places prescribe, on the left arm and on the forehead, and alleged these words as the commandment which they therein obeyed. But it seems more probable that the meaning is metaphorical, and that what is enjoined is rather a constant remembrance of the great deliverance, and a constant regulation of the practical life by it. For what is it that is to be 'a sign'? It is the Passover feast. And the 'therefore' of the next verse seems to say that keeping this ordinance in its season is the fulfilment of this precept. Besides, the expression 'for a sign,' 'for a memorial,' may just as well mean 'it shall serve as,' or 'it shall be like,' as 'you shall wear.' So I think we must say that this is a figure, not a fact; the enjoining of an object for thought and a motive for life, not of a formal observance. And it is very characteristic of the Jew, and of the universal tendency to harden and lower religion into outward rites, that a command so wide and profound was supposed to be kept by fastening little boxes with four slips of parchment containing extracts from the Pentateuch on arm and forehead. Jewish rabbis are not the only people who treat God's law like that. Even if literal, the injunction is for the purpose of remembering. Taking that meaning, then, the text sets forth principles that apply quite as much to us. You will observe 'hand,' 'eyes,' 'mouth'; the symbols of practice, knowledge, expression; work, thought, and word. Observe also that there is a slight change in construction in the three clauses; the two former are to be done in order that the latter may come to pass. Then the memorial of the great deliverance is to be 'on the hand' and 'before the eyes,' in order that 'the Lord's law' may be 'in the mouth.' Keeping these points in view-- I. God's great deliverance should be constantly before our thoughts. It is more than an accident that both Judaism and Christianity should begin with a great act of deliverance; that that act of deliverance should constitute a community, and that a memorial rite should be the centre of the ritual of both. The Lord's Supper historically took the place of the Passover. It was instituted at the Passover and instead of it. It is precisely the same in design, a memorial feast appointed to keep up the vivid remembrance of the historical fact to which redemption is traced; and not only to keep up its remembrance, but to proclaim the importance of extending that remembrance through all life.