[It is that] you believe in Allah and His Messenger and strive in the cause of Allah with your wealth and your lives. That is best for you, if you should know.
The Saheeh International Quran Translation
تُؤْمِنُونَ بِٱللَّهِ وَرَسُولِهِۦ وَتُجَٰهِدُونَ فِى سَبِيلِ ٱللَّهِ بِأَمْوَٰلِكُمْ وَأَنفُسِكُمْ ذَٰلِكُمْ خَيْرٌ لَّكُمْ إِن كُنتُمْ تَعْلَمُونَ[It is that] you believe in Allah and His Messenger and strive in the cause of Allah with your wealth and your lives. That is best for you, if you should know.