It is the only thing what she can give out. In this we she show her love to God with a pure heart..Also it shows her trust in God. Never mind what would happen, God is here in charge.

Juses tell his disciples to show what God really want human to do is never beyone His ability. We just to do all we can without any reserve and with joy and peace in Him. Trust in God and love Him need act out in our life, not with our lips.