John 5:21

“For as the Father raises the dead and gives them life, even so also the Son gives life to whoever he wishes.”

Thus just as the Father can raise the dead and give life, both now and in the age to come, so He, the Son, claims to have the same power and authority,  and to be able to do it by His own will. In other words He had the right to be able to do these things on His own. Nevertheless the context makes clear that He always exercises that will in line with His Father's will because they always work together. Jesus will reveal this power in the raising of Lazarus (chapter 11), which amazed everyone who witnessed it, but the statement goes much further than that. He is claiming to give eternal life to all who believe and to have the power to raise men at the last day. He is offering eternal life through the Spirit now, and will Himself be the One Who raises men at the last day (see John 5:28).