What does the Bible say about giving to God?

In Mark 12:41-44, Jesus observes those giving at the temple treasury and praises a poor widow who gave two mites, stating she contributed more than all the others because she gave all she had. This illustrates that God values the heart behind the gift rather than its monetary value. The widow's offering reflects genuine devotion and trust in God's provision, contrasting sharply with the large gifts given by the wealthy, which were given from their abundance and lacked sacrificial significance.