All authority has been given to Me in heaven and on earth

Matthew 28:18-19
And Jesus came and spoke to them, saying, “All authority has been given to Me in heaven and on earth. 19 Go therefore[c] and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 

To obey and go on the mission directed by God, requires us to have Him always in mind. Namely, we must remember that we will be going in His Authority and since He is Sovereign, this is very powerful indeed. To know His authority, we need to know Him more ourselves, we need to be close to our Lord Yshua. One way of doing this is to abide in Him, that is to live according to His words and become a living witness to others.