The Most Rev Justin Welby told worshippers at Canterbury Cathedral that the attacks risked "causing us to act fearfully, to see a world in which fear triumphs".
But he also said: "On Easter Day hope decisively overcame fear".
Tuesday's bombings in Brussels killed 28 people and injured dozens.
The archbishop said hope can seem far away and fear so close "in the shadow of this week's darkness".
"Fear is reasonable, a normal human reaction," he added.
Pope delivers Easter message of hope
PM praises UK's 'Christian values'
"Easter proclaims to us in flesh and blood that fear and death and terror are not the last words.
"God has spoken life, hope and purpose.
"Terror speaks of a world at war with itself, of faiths at each others' throats.
"Jesus Christ reaches out not in exclusion but in embrace; this is the feast of the victory of God, and we celebrate in the midst of darkness, by our worship and praise shining an unquenchable light."

The girl, called Nieve, was attending the Handmade Parade in Hebden Bridge on Sunday with her grandparents when the dog jumped up and bit her.
She needed eyelid surgery and suffered "potentially irreparable damage" to a tear duct.
The man in the e-fit is described as being broad, bald and aged about 50.
A second man, also thought to be about 50 and of similar build, was present at the time of the incident, West Yorkshire Police said.
Both men left the scene without checking on the girl's welfare or leaving any details.
The dog, believed to be a Staffordshire bull terrier, was on a lead at the time of the incident and is described as brindle and white coloured.
PCSO Gareth Helliwell said: "The five-year-old girl involved in this incident needed reconstructive surgery to an eyelid following this attack and has suffered potentially irreparable damage to her lower tear duct."
The girl's family described the dog's owner as "scum", adding "she could have lost her eye, she was covered in blood and the guy just ran off, it's cowardly".
She was also bitten on the ankle despite the dog being pulled away on a lead, they said.
Police appealed for anyone with information about the dog or the two men with it to contact them.

They left Budapest station on foot after a stand-off with police, defying official efforts to take them to reception centres and register them.
Earlier on Friday another group escaped along railway tracks in Bicske, to the west, from a train stopped by police.
European Union states are struggling to agree on how to deal with the crisis.
The surprise announcement by Prime Minister Viktor Orban's chief of staff late on Friday night followed several days of chaotic scenes.
Janos Lazar said Hungary would offer buses to those walking along the main motorway to Vienna, as well as to migrants still at Budapest's Keleti railway station.
The buses would take people to Hegyeshalom, on the border with Austria.
Hungary had not yet had a response from the Austrian government so he did not know whether they would be allowed in to Austria, he added.
"We are taking this step so Hungary's transportation is not paralyzed during the next 24 hours," Mr Lazar said, according to the Associated Press.
It was unclear whether migrants would be happy to get on the buses, after several hundred were encouraged to get on a train on Thursday that did not then head to Austria.
The BBC's Matthew Price, walking with the migrants, said that as night fell, many continued to walk, but others - including a family with five children - appeared to stop for the night on the hard shoulder, or in adjacent fields.
Hungary has become a major transit nation for people fleeing the Middle East and Africa, seeking to reach north and west Europe.

The 27-year-old was caught on camera apparently swearing at Murray's semi-final opponent Tomas Berdych's team.
Murray had defended Sears, saying: "In the heat of the moment, you can say stuff that you regret."
But Sears made light of the issue for the final against Novak Djokovic.
The Archbishop of Canterbury has warned people not to give in to fear after the attacks in Brussels, in his Easter Sunday sermon.
[NEXT_CONCEPT]
Police have issued an e-fit of a man they want to trace in connection with a dog attack on a five-year-old girl.
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Hungary is to send buses to transport migrants to Austria's border after more than 1,000 began walking there earlier on Friday.
[NEXT_CONCEPT]
Andy Murray's fiancee Kim Sears laughed off the controversy over her colourful language in Melbourne by wearing a 'Parental Advisory: Explicit Content' T-shirt to the Australian Open final.