Having (first) settled a thing in mind, it is then expressed in words and is ultimately given effect to by (external) acts. My (own) mind is a proof of this.
मनसा निश्चयं कृत्वा ततो वाचाभिधीयते। क्रियते कर्मणा पश्चात् प्रमाणं मे मनस्ततः॥