Adam Clarke's Bible Commentary-9 Verse 7-9. On this account of the Baptist's mode of preaching, see the notes on Matt. iii. 7-11.
John Gill's Bible Commentary
Ver. 9. And now also the axe is laid unto the root of the trees , etc.] Not only to Jesse's family, which as a root in a dry ground, and to Jerusalem, the metropolis of the nation; but to the root of the vain boasting of every Jew; their descent from Abraham, the covenant made with him, their ecclesiastical state and civil polity, all which would quickly be at an end: the Romans were now among them, the axe in God's hand; by means of whom, utter ruin and destruction would be brought upon their nation, city, and temple: every tree therefore which bringeth not forth good fruit is hewn down, and cast into the fire; (See Gill on Matthew 3:10).
Matthew Henry Commentary
Verses 1-14 - The scope and design of John's ministry were, to bring the people from their sins, and to their Saviour. He came preaching, not a sect, or party, but a profession; the sign or ceremony was washing with water By the words here used John preached the necessity of repentance, i order to the remission of sins, and that the baptism of water was a outward sign of that inward cleansing and renewal of heart, whic attend, or are the effects of true repentance, as well as a professio of it. Here is the fulfilling of the Scriptures, Isa 40:3, in the ministry of John. When way is made for the gospel into the heart, by taking down high thoughts, and bringing them into obedience to Christ by levelling the soul, and removing all that hinders us in the way of Christ and his grace, then preparation is made to welcome the salvatio of God. Here are general warnings and exhortations which John gave. The guilty, corrupted race of mankind is become a generation of vipers hateful to God, and hating one another. There is no way of fleeing from the wrath to come, but by repentance; and by the change of our way the change of our mind must be shown. If we are not really holy, both i heart and life, our profession of religion and relation to God and his church, will stand us in no stead at all; the sorer will ou destruction be, if we do not bring forth fruits meet for repentance John the Baptist gave instructions to several sorts of persons. Thos that profess and promise repentance, must show it by reformation according to their places and conditions. The gospel requires mercy not sacrifice; and its design is, to engage us to do all the good we can, and to be just to all men. And the same principle which leads me to forego unjust gain, leads to restore that which is gained by wrong John tells the soldiers their duty. Men should be cautioned against the temptations of their employments. These answers declared the presen duty of the inquirers, and at once formed a test of their sincerity. A none can or will accept Christ's salvation without true repentance, s the evidence and effects of this repentance are here marked out.
Greek Textus Receptus
ηδη 2235 ADV δε 1161 CONJ και 2532 CONJ η 3588 T-NSF αξινη 513 N-NSF προς 4314 PREP την 3588 T-ASF ριζαν 4491 N-ASF των 3588 T-GPN δενδρων 1186 N-GPN κειται 2749 5736 V-PNI-3S παν 3956 A-NSN ουν 3767 CONJ δενδρον 1186 N-NSN μη 3361 PRT-N ποιουν 4160 5723 V-PAP-NSN καρπον 2590 N-ASM καλον 2570 A-ASM εκκοπτεται 1581 5743 V-PPI-3S και 2532 CONJ εις 1519 PREP πυρ 4442 N-ASN βαλλεται 906 5743 V-PPI-3S
Vincent's NT Word Studies
9. See on Matt. iii. 10.