s it true? Is forgiving others, without more, enough to have our own sins forgiven?
You have two issues here.
How are we forgiven/forgive others?
and
What effect does forgiveness have?
How are we forgiven by God?
Through out the bible Gods forgiveness is conditional on repentance. The Israelites in worship had to take a sacrifice, lay there hand on it and kill it.
The act of taking a sacrifuce was an act of reptance.
In the giving of the Laws at Sini, God warned them of the consquence of disobeying him and told them what they would have to do. ' Turn from their wicked ways, that is repent.
God only forgives us on our repentance, he is our pattern. Those who offend/sin against us are to be forgiven on their repentance. Then we have no choice we Must forgive. No matter how often they offend us.
The unrepentant offender, we like Jesus on the cross, hand over to God for him to deal wth us, the offender etc.
Then we are to pray for them intelligently.
Does forgiveness have an effect?
Well it restores brocken relationships, is far better for one than harbouring recentment, but forgiveness has to be real. It cannot be manufactured, it is not a feel good fuzzy feeling.
So can a non christian, because they are forgiving get into heaven? Answer no.
Access to heaven is through faith in Jesus, not because someone is forgiving of others, it is whether there sins have been forgiven and that only happens if they have repented.