Jos 1:6
There are two kinds of strength and courage. There is animal strength and there is moral strength; there is animal courage and there is moral courage. And although the strength of active limbs and firm muscles and the courage which men share with the lower animals are not to be despised, but praised and sought after in their degree, yet it is to the nobler qualities the text chiefly refers when it says, "Be strong and of a good courage."
I. The need of strength and courage. God gave this word of good cheer to Joshua, and repeated it thrice over, so that he might never forget it. Joshua and his men needed it, or God would not have said it to him thrice so earnestly. You will need to hear this cheering cry: (1) in the hour of confession; (2) in the hour of temptation; (3) in the hour of misfortune; (4) in the hour of death.
II. The source of strength and courage. "Be not afraid, neither be thou dismayed, for the Lord thy God is with thee whithersoever thou goest." This is the secret. It is to have God ever near, a Friend unseen to others, but visible to us. Christ with us that will make us strong and courageous. He knows all the dangers that are before us. Our enemies are strong the wicked heart, the tempting world, the unknown future. But greater is He that is with us than they that are with them. No power can stand against us if He is on our side. And, best of all, He loves us. If we know that Christ loves us and that He has all power and knows all that is before us, what have we to fear?
J. Stalker, The New Song, p. 141.
Jos 1:9
This expression "Be strong" does not mean "Be strong in body," but "Be strong in mind; " "Be strong in spirit;" "Be brave."
An order like this could not have been a mere mockery, an order which Joshua was unable to obey. The word which bade him be strong was an assurance at the same time that if he would, he might be strong according to his day.
I. The first secret of true courage is to know and be sure that we have some power. Hence the wisdom of the maxim of the ancients, "Know thyself" learn to see what thy real capacity is, and knowing that, shrink not from venturing on putting it to the proof. It is not too much to say that all men go wrong by underestimating themselves? For what deeper self-depreciation is there than for a man to live in the world forgetful of what he is brought here for forgetful of his Christian privileges, of his Christian name, of his Christian freedom?
II. We all have some power; the question is, How much and what? That is the question we should ask ourselves every day; it is the great question of our early life especially, for on the right answering of it all our success depends. Our weaknesses guarded against often become our strength; and our best lessons, if we heed them, are our mistakes. Joshua's strength was a knowledge of his weakness. Beware of thinking you have no strength because you are not omnipotent. God says to us all, whatever worthy work we are entering upon, "Be of good courage; be strong!"
A. Jessopp, Norwich School Sermons, p. 97.
References: Jos 1:9 . J. Ellison, Christian World Pulpit, vol. xv., p. 305; Congregationalist, vol. vii., p. 400. Jos 1:16-18 . Parker, Pulpit Analyst, vol. i., p. 626. 1, etc. G. Gilfillan, Alpha and Omega, vol. i., p. 156. 2 A. Saphir, Found by the Good Shepherd, p. 383.