They are the same thing at different stages. PAYE is how your employer pays income tax monthly on your behalf. If over-deducted, SARS refunds you when you file.
Pension and RA contributions reduce your taxable income — the number SARS uses to calculate tax. Limit: 27.5% of salary or R430,000/year.
SARS gives R376/month credit for yourself and first dependant, R254 for each additional. 2 members saves R752/month in tax regardless of income.