Joshua 1:3 (ESV) 3 Every place that the sole of your foot will tread upon I have given to you, just as I promised to Moses.
Notice the 'have given to you' in this incredible verse. From what I can tell from looking at other translations, this is the better translation of the Hebrew. The NIV slightly contracts the verse by saying, 'I will give you every place where you set your feet...'. In essence those translators thought they were saying the same thing but I don't think it is.
The word 'have' as opposed to 'will' makes a big difference. What God was actually saying to Joshua was, 'I have already given you this land. It's a done deal. Now it's up to you to walk into this land and possess it. Everywhere where you put your feet in this land, I have already given to you'. Because God had already given it to him, all he had to do was to actually walk into/claim/inherit all that was already theirs in God's economy. There would be set-backs, opposition, criticism, grumbling and complaining but ultimately no-one would be able to stand against them because it was already settled in heaven. God tells Joshua this a few times in Joshua chapter 1.
This really speaks to me for the 'land' that God has given me...and you. What has God put in your heart to 'walk into'? What is your 'land'? Whatever He has put in our heart, He has already given us. He is waiting for us to step into that calling so that He can say to us, 'Every place that the sole of your foot will tread (in that particular area of calling) I have given you.'
No set-back, no opposition, no criticism, no lack, no grumbling and complaining can thwart what God has given us. There is only one exception to this litany of 'no .....' and that is 'I'. I can thwart what God has given me through not meditating on God's word, through not walking God's way, through fear, through dismay, and through not constantly being filled with the Spirit.
Note that God tells Joshua three times to be strong and courageous, and the tribesmen around him echo it back to him a fourth time. God is saying it to you, those around you are echoing it to you in the hope that you will take them into the 'land' that God has given you, 'Be strong and courageous'!