God has promised an end to tears, death, sorrow, crying, and pain. It's in the Bible, Revelation 21:4, TLB. "He will wipe away all tears from their eyes, and there shall be no more death, nor sorrow, nor crying, nor pain. All of that has gone forever."
Heaven will be a place of joy forever. It's in the Bible, Isaiah 35:10, TLB. "These, the ransomed of the Lord, will go home along that road to Zion, singing the songs of everlasting joy. For them all sorrow and all sighing will be gone forever; only joy and gladness will be there."
Grief does not last forever. It's in the Bible, Psalm 30:5, TLB. "Weeping may go on all night, but in the morning there is joy."
God keeps track of every tear. It's in the Bible, Psalm 56:8, NKJV " You number my wanderings; Put my tears into Your bottle; Are they not in Your book?"
God will heal your grief. It's in the Bible, Psalm 147:3, TLB. "He heals the brokenhearted, binding up their wounds."
Jesus promised a Comforter. It's in the Bible, John 14:16, TLB. "If you love Me, obey Me; and I will ask the Father and He will give you another Comforter [the Holy Spirit], and He will never leave you."
Accept the promise of peace. It's in the Bible, John 14:27, TLB. "I am leaving you with a gift—peace of mind and heart! And the peace I give isn't fragile like the peace the world gives. So don't be troubled or afraid."
Hope in the future resurrection provides comfort in grief. It's in the Bible, I Thessalonians 4:13-17, NKJV. "But I do not want you to be ignorant, brethren, concerning those who have fallen asleep, lest you sorrow as others who have no hope. For if we believe that Jesus died and rose again, even so God will bring with Him those who sleep in Jesus. For this we say to you by the word of the Lord, that we who are alive and remain until the coming of the Lord will by no means precede those who are asleep. For the Lord Himself will descend from heaven with a shout, with the voice of an archangel, and with the trumpet of God. And the dead in Christ will rise first. Then we who are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air. And thus we shall always be with the Lord. Therefore comfort one another with these words."
The dead will live again. It's in the Bible, John 5:28-29, TLB. "Don't be so surprised! Indeed the time is coming when all the dead in their graves shall hear the voice of God's Son, and shall rise again—those who have done good, to eternal life; and those who have continued in evil, to judgment."