Take good heed - unto yourselves that ye love the Lord - לנפשתיכם lenaphshotheychem, Take heed To Your Souls, literally; but נפש nephesh and nefs, both in Hebrew and Arabic, signify the whole self, as well as soul and life; both soul and body must be joined in this work, for it is written, Thou shalt love the Lord thy God with all thy heart, soul, mind, and strength.

Take good heed therefore unto yourselves,.... To be upon their guard, and to be watchful, were very necessary to them, that they might not be ensnared by the Canaanites, and drawn aside by them into idolatry, and so apostatize from the Lord and his worship, since their temptations would be many:
that ye love the Lord your God; which would the most strongly influence and engage them to serve and worship the Lord, and obey his commands, and be the best preservative against idolatry and false worship.

Would we cleave to the Lord, we must always stand upon our guard, for many a soul is lost through carelessness. Love the Lord your God, and you will not leave him. Has God been thus true to you? Be not you false to him. He is faithful that has promised, Hebrews 10:23. The experience of every Christian witnesses the same truth. Conflicts may have been severe and long, trials great and many; but at the last he will acknowledge that goodness and mercy followed him all the days of his life. Joshua states the fatal consequences of going back; know for a certainty it will be your ruin. The first step would be, friendship with idolaters; the next would be, marrying with them; the end of that would be, serving their gods. Thus the way of sin is down-hill, and those who have fellowship with sinners, cannot avoid having fellowship with sin. He describes the destruction he warns them of. The goodness of the heavenly Canaan, and the free and sure grant God has made of it, will add to the misery of those who shall for ever be shut out from it. Nothing will make them see how wretched they are, so much, as to see how happy they might have been. Let us watch and pray against temptation. Let us trust in God's faithfulness, love, and power; let us plead his promises, and cleave to his commandments, then we shall be happy in life, in death, and for ever.

Take good heed, therefore, that ye love the Lord your God--The sum of his exhortation is comprised in the love of God, which is the end or fulfilment of the law (Deuteronomy 6:5; Deuteronomy 6:11:13; Matthew 22:37).

Take heed - Now it requires more watchfulness and diligence than it did in the wilderness, because your temptations are now stronger; from the examples and insinuations of your bad neighbours, the remainders of this wicked people; and from your own peace and prosperity: and the pride, security, forgetfulness of God, and luxury, which usually attend that condition.