In Nehemiah, chapter four, verse twenty, when our work for God is genuinely undertaken in faith and humility to bring God glory and to advance His kingdom, using the weapons of the Spirit, we can rest assured that no matter how great the difficulties, God will fight for us.
We must watch always against spiritual enemies and not expect that our warfare will be over till our work ends. The word of God is the sword of the Spirit, which we ought to have always at hand and never to have to seek it either in our labors or in our conflicts as Christians. Every Christian is both a laborer and a soldier, working with one hand, and fighting with the other. Good work is likely to go on with success when those who labor in it make a business of it.
And Satan fears to assault the watchful Christian, or, if attacked, the Lord fights for him. Therefore, must we wait to the close of life, never putting off our armor till our work and warfare are ended; then we shall be welcomed to the rest and joy of our Lord.