I heard the Messenger of Allah ﷺ say: “Action is but by intention and each person will have but that which he intended. So whoever migrated for the sake of Allah and His Messenger, then his migration was for the sake of Allah and His Messenger, whoever migrated for some worldly purpose or for the sake of a woman whom he could marry, his migration was for the purpose for which he migrated.” (Using translation from Aḥmad 300)   

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ إِنَّمَا الْأَعْمَالُ بِالنِّيَّةِ وَإِنَّمَا لِامْرِئٍ مَا نَوَى فَمَنْ كَانَتْ هِجْرَتُهُ إِلَى اللهِ وَإِلَى رَسُولِهِ فَهِجْرَتُهُ إِلَى اللهِ وَإِلَى رَسُولِهِ وَمَنْ كَانَتْ هِجْرَتُهُ إِلَى دُنْيَا يُصِيبُهَا أَوِ امْرَأَةٍ يَتَزَوَّجُهَا فَهِجْرَتُهُ إِلَى مَا هَاجَرَ إِلَيْهِ  

[Machine] I heard Shafi'i, may Allah have mercy on him, say that deeds are judged based on intentions, which constitutes one-third of knowledge.  

سَمِعْتُ الشَّافِعِيَّ رَحْمَةُ اللهِ عَلَيْهِ يَقُولُ يَدْخُلُ فِي حَدِيثِ الْأَعْمَالُ بِالنِّيَّاتِ ثُلُثُ الْعِلْمِ