Every programme of God involves the use of money and materials. For example the construction of Tabernacle in the desert – Ex. 35:5, the building of the Temple both of Solomon and Ezra, the rebuilding of the wall of Jerusalem by Nehemiah, the running and sustenance of the program of the early Church – Acts 2:41, support of missionary teams in the early Church and beyond.
God has always used His people for whom He first makes provision, then places a demand on them. Usually, God asks for, loves and blesses cheerful givers.
As it was then, so it is even more today. Missionaries need financial and material support to effectively discharge their ministry.