Isaiah 35:6

Then shall the lame [man] leap as an hart..... As the lame man did healed by Peter, Acts 3:1 there were many instances of such persons cured by Christ when here on earth, Matthew 15:30 and in a spiritual sense this was verified in many who were impotent to that which is good; had neither will nor power to go to Christ for life and salvation, nor to walk by faith in him, nor to walk in his ways; who yet, by the mighty power of the Spirit and grace of God, became able and willing to go to him, and venture their souls on him; walked on in him as they had received him; and not only walked in his ways, but ran in the ways of his commandments, and leaped for joy for what they saw and heard of him, and received from him; and innumerable will be the instances of such mighty grace at the spiritual coming and reign of Christ:

and the tongue of the dumb shall sing; this had its accomplishment, in a literal sense, at the first coming of Christ, Matthew 9:32

Matthew 12:22 and, in a spiritual sense, in many who before had nothing to say to God in prayer, nor in praise; nothing to say of Christ, or for him; or of the blessed Spirit, and his divine operations; but now, by divine grace, are made to speak unto God, both in a petitionary way, and in a way of thankfulness; and of Christ, and of the blessed Spirit; and of the great things each have done for them; and even to sing for joy, because of the wondrous blessings of grace they were made partakers of; and many more such there will be in the latter day, when the Spirit is poured down from on high. Kimchi interprets all this of the Israelites, who were in captivity as blind, deaf, lame, and dumb. So the Targum of this and the preceding verse Isaiah 35:5,

"then shall the eyes of the house of Israel be opened, who were as blind men as to the law; and the ears of them that are as deaf men, to attend to the words of the prophets shall hear; then when they shall see the captives of Israel gathered to go up to their own land as the swift harts, and not tarry,'' c.

but it may be better applied to their present state, and to their case when they shall be turned to the Lord in the latter day:

for in the wilderness shall waters break out, and streams in the desert; not literally, but mystically; and may be understood both of the doctrines of the Gospel breaking out in the ministry of them, in such places as were like unto the wilderness and desert, quite barren, and destitute of the knowledge, grace, and fear of God; see Joel 3:18 and of the abundance of grace, and the efficacy of it, making the word effectual to the conversion and fruitfulness of multitudes of souls, bringing along with it a vast variety of spiritual blessings; see John 7:37 to both which, the one as the means, and the other as the cause, all the above wonderful things are owing.