He will make 19 speeches during his tour of Kenya, Uganda and the Central African Republic (CAR) and they will probably address these issues:
He is expected to focus on religious tolerance and peaceful coexistence at a time of rising political instability and extremism in much of the region.
Security is expected to be tight throughout the trip, as the faithful flock to see this popular Pope, who has previously said that Christians would be wrong to equate Islam with violence.
His first stop, Kenya, has seen some of the worst Islamist violence: Two years ago, gunmen from the Somali militant group al-Shabab massacred at least 67 people inside Nairobi's Westgate shopping mall.
In Uganda, his second stop, al-Shabab bombed sports bars in Kampala where fans were watching the 2010 football World Cup on TV.
Many think the third stop on his trip, the CAR, is too dangerous for him to visit.
The Pope's visit to the capital, Bangui, where many have died in violence between largely Muslim Seleka rebels and mainly Christian "anti-balaka" militias, is seen as his most dangerous yet - but potentially also one of his most fruitful as a peace-maker.
In short: He will probably urge Christians and Muslims to get along.
2. Poverty
This is a Pope who has been hailed as the champion of a church for the poor.
His emphasis on the developing world, and the example of simplicity he sets in his own life, will be welcomed in countries where corruption in public life is often seen as an issue.
His capacity to look beyond Europe and embrace the concerns of people around the world is also likely to endear him to the faithful, and to those of other faiths, as this Pope from the southern hemisphere offers a message of hope to the dispossessed, and the struggling.
In Kenya, 75% of the wealth is owned by around 1% of the population, so Pope Francis's message may well prove popular among many of the remaining 99%.
He is likely to criticise inequality and corruption and will visit Kenya's multi-ethnic Kangemi slum - home to around 100,000 people.
In short: He will probably criticise corruption and inequality.
With international climate change talks starting in Paris on 30 November, many will be listening closely to what Pope Francis has to say when he speaks in Nairobi to the UN's Environment Programme.
His encyclical on the environment, "Laudato Si" published earlier this year, raised hackles among big business in the US with its apocalyptic warning that humankind risks turning the earth into a "vast pile of filth" by mistreating the planet.
The Pope is unlikely to mince his words.
He will probably emphasise the need for the developed world to stop abusing the planet for profit and to the detriment of the poor, whom he sees as the victims of climate change.
In short: He will probably tell big business to think of the poor.
LGBT (lesbian, gay, bisexual and transgender) activists, especially in Uganda, would like the Pope to encourage greater tolerance and speak out against the criminalisation of homosexuality in many African countries.
In the past, when the Pope was asked about a gay priest he said, "Who am I to judge?"
However, the recent Synod on the Family in Rome did not budge on the issue of greater acceptance within the Church for gay Catholics.
Might he directly address the discrimination against gay and lesbian communities on a continent where being gay is often still a crime? Activists certainly hope so.
They think it could make an enormous difference to attitudes in the continent.
Attitudes like that of Guinean Cardinal Robert Sarah who told the Synod that what Nazi and Communist ideology were to the 20th Century, so the twin "beasts" of "Western homosexual and abortion ideologies, and Islamic fanaticism" were for the 21st.
In short: He is unlikely to lecture Africa on LGBT rights.
The Pope once said that Catholics did not have to breed "like rabbits", before the Vatican clarified his remarks to insist that he was not speaking out against large families.
However, many international aid agencies and some Western governments would like the Roman Catholic Church to give up its opposition to artificial contraception, especially its ban on the use of condoms, to help people on a continent where Aids/HIV remains a problem.
Pope Francis is likely to meet people with HIV, but unlikely to budge on contraception.
Large Catholic families are helping to ensure that Africa becomes an ever more important part of the Church.
And the Synod on the Family in October reiterated the Church's hostility towards aid programmes that try to link development aid to the use of artificial contraception.
In short: He is unlikely to scrap the Catholic ban on contraception.
Five African countries with the most Catholics:
1. Democratic Republic of Congo: 31 million
2. Nigeria: 20 million
3. Tanzania: 14.2 million
4. Uganda: 14.1 million
5. Angola: 10.8 million
Christianity is projected to be sub-Saharan Africa's largest religious group by 2050 with 1.1bn followers from 517 million in 2010. The Muslim population is expected to grow at faster rate, rising from 248 million to 670 million.
Source: Pew research centre
Pope Francis will go to Africa for the first time this week, visiting a refugee camp, a slum and a mosque.