Read and reflect on verse 463 from Surah Aal-i-Imraan: exulting in that [martyrdom] which God has bestowed upon them out of His bounty. And they rejoice in the glad tiding given to those [of their brethren...
فَرِحِينَ بِمَا آتَاهُمُ اللَّهُ مِنْ فَضْلِهِ وَيَسْتَبْشِرُونَ بِالَّذِينَ لَمْ يَلْحَقُوا بِهِمْ مِنْ خَلْفِهِمْ أَلَّا خَوْفٌ عَلَيْهِمْ وَلَا هُمْ يَحْزَنُونَ
exulting in that [martyrdom] which God has bestowed upon them out of His bounty. And they rejoice in the glad tiding given to those [of their brethren] who have been left behind and have not yet joined them, that no fear need they have, and neither shall they grieve: