Isaiah 2:3

And many people shall go and say
This is a prophecy of the numerous conversions among the Gentiles in the latter day, and agrees with ( Zechariah 8:20-23 ) and even the author of the old Nizzachon

Come ye, and let us go up to the mountain of the Lord, and to the
house of the God of Jacob;
the church of Christ, so called; (See Gill on Isaiah 2:2). This expresses the concern that truly gracious souls have for the house of God, and his worship in it; they go up to it, considering it both as their duty and their privilege; and which they do frequently and constantly, with much spiritual pleasure, though sometimes with difficulty, finding their account in it, and knowing it is for the glory of God; and not content with so doing themselves, they encourage others to do so likewise; either professors of religion with them, who are negligent and backward through a spirit of slumber and slothfulness on them; through lukewarmness, coldness, and leaving their first love; through an over love to the world, and the things of it; and through a vain conceit of themselves, as being as knowing as their teachers, or wiser than they: or else such who have made no profession, who are quite ignorant of divine things, these they endeavour to bring with them, out of love to their souls, that they may be under the means of grace, in order to their conversion; and such as are inquiring the way to Zion, with their faces toward it, these they encourage to join with them in holy fellowship; and in all they set an example by a constant attendance themselves; they do not stir them up to go alone, either one or other, but propose to go with them. See ( Psalms 122:1 )

and he will teach us of his ways:
that is, the Lord the God of Jacob, the covenant God and Father of his church and people, who often in this prophecy go by the name of Jacob; he is the teacher, and there is none teacheth like him; and happy are they who are taught of God, and who have heard and learnt of the Father, and come to Christ: he taught men by his Son, when here on earth; who was a teacher that came from God, taught the way of God in truth, and with authority, as the Scribes and Pharisees did not: and then by his Spirit, sent after him to teach all things, and bring all things to remembrance; and since by his apostles and ministers, who have gifts, and a commission to teach men; though all human teachings are of no avail, without a divine blessing, unless accompanied with the anointing, which teacheth all things; and which will be abundantly bestowed in the latter day, when all the children of Zion, and that come to the house of the Lord, will be taught of God. Kimchi says, the teacher here is the King Messiah; the "us" to be taught are Gentiles, aliens from the commonwealth of Israel, and strangers to the covenants of promise, whom Christ, under the Gospel dispensation, has given his ministers a commission to teach; and here design such as are humble souls, and sensible of their ignorance, and who know something of Christ, and believe in him; yet, as they know but in part, they desire to know more. The things taught them are the "ways" of the Lord; his ways of love, grace, and mercy, in the salvation of men; the steps he took in eternity towards it, by consulting and contriving the best method of it, forming it in his Son, and agreeing with him in covenant about it, and choosing the persons in him he designed to save: and also his goings forth in time, by sending his Son into this world, to obtain salvation for them, and his Spirit into their hearts, to apply it to them; likewise the ways which he prescribes and directs his people to walk in, such as the ordinances of the Gospel, and every path of duty: and the place where these are taught is the church of God, and to this school all that desire to learn should go; and there is ever something more and more of these ways to be learnt; for they are not all learnt at once, only part of his ways; and it is but a small portion, we know of these in the present state, which God has taken in order to bring about our salvation.

And we will walk in his paths;
in Christ, the way, by faith, and in all his ordinances and paths of duty, according to the rule of his word; in imitation of him, and as he walked; in a dependence on his wisdom, grace, and strength, continuing therein; for walking is a progressive motion, and designs a series and course of obedience and perseverance in it:

for out of Zion shall go forth the law, and the word of the Lord
from Jerusalem;
by which is meant the law or doctrine of the Messiah, ( Isaiah 42:4 ) for the Hebrew word (hrwt) signifies any doctrine, and so the evangelical one, the law or doctrine of faith, of justification by faith in Christ's righteousness, ( Romans 3:27 Romans 3:28 ) together with all other doctrines of the same kind; called the "word of the Lord", which the Lord Christ is the author, preacher, sum, and substance of; the word of righteousness, peace, reconciliation, life, and salvation by him. This first began according to his commission and direction to be preached at Jerusalem, and from thence it went forth into all the world; and it is in Zion, in the church of God, it is now preached, and will be more clearly and fully in the latter day; and so is an argument and an encouraging reason to engage persons to go up thither and hear it.

F16 Apud Wagenseil. Tela ignea, p. 29.