Prayer is the breath of the soul. God's will is that we rejoice in Jesus and pray without ceasing.
When sin blocks us from prayer, it's like we stop breathing. The parable of the sower offers three explanations for why this can happen. But ultimately, to keep the faith until the end, we need to pray, obey God, and read Scripture.
When we walk without sin and pray constantly, great freedom abounds in our hearts. We're now free to love others. Keeping God's commandments is a joy. Christ lives unhindered in us. Thus, we bear fruit: some thirty, some sixty, and some one hundred fold!